Psoriasis Vulgaris
Psoriasis Vulgaris
Systemic treatments used to treat psoriasis are summarized in Table 5.
Screening Before Administration of Biologic Therapy. Before starting a patient on any biologic drug, much needs to be assessed by a history and physical examination, laboratory tests have to be analyzed (see Table 6 and Table 7), and a closer follow-up must be considered. Though mostly well tolerated without significant side effects and because of the extensive follow-up required with their use, many PCPs will use biologics, working in conjunction with dermatologists who are familiar with their use. Drug allergies and current medications (dermatological and others) should be assessed, looking for those medicines that may increase immunosuppression or may exacerbate the psoriasis. In addition, a patient's medical history should be carefully evaluated and medicine regime reconciled to ensure that if the patient were to start taking a biologic drug, there would be as few interactions as possible. For example, reports of hypoglycemia in patients taking etanercept warrant a reduction of antidiabetic dosing and monitoring of glucose logs by PCPs for some of these patients. Because some patients who have plaque psoriasis have untreated antistreptolysin O titers from guttate psoriasis (that developed into plaque psoriasis), it always is a good idea to check an antistreptolysin O titer for every patient with new psoriasis.
Vaccines. Since patients taking these therapies may not receive live or live-attenuated vaccines (measles, mumps, rubella; oral polio vaccine; varicella zoster vaccine [VZV]; Bacillus Calmette-Guérin; yellow fever; and influenza [nasal]), ensuring that these patients are up to date with their age-appropriate vaccines is important. Annual inactivated influenza and pneumococcal (at least one dose, if necessary) vaccines should be given since these biologic drugs can lower the immune system's ability to fight infection. Vaccination for hepatitis A and B also are recommended before beginning a biologic. It usually takes 2 to 6 weeks for the body to produce a significant amount of antibodies after immunization.
Other Risks. Lymphoma and Leukemia: Lupus-like symptoms (butterfly sun-sensitive rash, oral ulcers, etc.) can be a side effect of using tumor necrosis factor (TNF)-α inhibitors. Some biological drugs also increase antinuclear antibody titers, so establishing a baseline antinuclear antibody titer is optional. Biological drugs can also increase the risk of cancer, mostly lymphoma and leukemia; however, it is uncertain whether it is the psoriasis or the initiation TNF-α blocking treatment that is the causative factor. According to some studies, many of the original clinical trials conducted using adalimumab and etanercept in patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, and psoriasis showed a 3-fold higher rate of lymphoma compared with the general US population. However, when meta-analyses of these randomized controlled trials were considered, most of the patients who populated the original trials were from cohorts with rheumatoid arthritis and Crohn's disease, which usually combined biological therapies with additional immunosuppressive agents, therefore introducing selection bias and confounding. In the absence of TNF-α blocking therapy, patients with moderate to severe rheumatoid arthritis, for example, have a 5- to 25-fold increased risk of developing lymphoma. It is therefore unclear whether the increases in the rate of lymphoma observed in these trials were related to TNF-α blocking therapy.
Congestive Heart Failure/Cardiac Events: Because signs and symptoms of congestive heart failure can worsen while taking a biologic drug like a TNF-α inhibitor, physicians should monitor these patients carefully and weigh the risk-to-benefit ratio. Major adverse cardiovascular events have been seen with the use of interleukin-12/23 inhibitors, namely briakinumab, which was pulled from clinical trials. Ustekinumab data also show some events, but further research is needed to clarify the role that these drugs may play in risk of major adverse cardiovascular events and the mechanism by which they may occur. The rate of major adverse cardiac events in patients taking ustekinumab was no greater than rates in both the general population and a population with psoriasis. Ustekinumab can cause reversible posterior leukoencephalopathy syndrome, which presents as a persistent headache, seizures, sudden vision changes, and mental and mood changes, so establishing a neurological history and physical examination at baseline is important.
While the risk of potential reactivation of VZV is very low when a patient is taking a biologic drug, the risk increases when this patient is also taking oral prednisone for a comorbidity. Reactivation of VZV can lead to a potentially serious neurological complication, and VZV vasculopathies in immunocompromised patients have been described in the literature. In these cases the patient should be closely monitored for and educated about any signs or symptoms of stroke or transient ischemic attack and administration of VZV intravenous immunoglobulin should be considered.
Basic Pharmacology of Biologicals. The half-life of etanercept is 4 days, that of adalimumab is 10 to 20 days, infliximab is 8 to 9.5 days, and ustekinumab is 14.9 to 45.6 days; the time required for any of these drugs to be removed from the body once they are discontinued is approximately 4 to 5 half-lives. Once a patient begins taking a biologic drug, its important to closely follow them for drug-related adverse events. Reasons to stop a biologic drug are serious infection; severe persistent neurological symptoms such as headache, eye pain, loss of vision in one eye, or numbness; Guillain-Barré syndrome; lymph node swelling; unintended weight loss; malaise; easy bruising; bleeding; pallor; or serious allergic reaction such as anaphylaxis or angioedema.
Indications and Dosing. Because of the significant cost of biologics, more traditional medications should be tried first, if possible, and biologics used only when those fail or there is a contraindication to oral systemic therapy.
This drug should be completely avoided in women of childbearing age because it is teratogenic and category X. Although acitretin may take 2 months to be eliminated from the body, when alcohol is consumed, eretinate, its metabolite, can have a half-life of up to 168 days. It is recommended that women abstain from consuming alcohol in any form while taking the drug and for at least 2 months after it is discontinued because the amount of metabolite is directly proportional to the amount of alcohol ingested. In fact, the teratogenic effects can occur for up to 2 to 3 years after acitretin discontinued in a patient who has consumed alcohol. Because of this, it is advised that if prescribing this for women of childbearing age, they must (1) have 2 negative urine or serum pregnancy tests before receiving their first dose of acitretin; (2) have monthly pregnancy tests before receiving their acitretin prescriptions; (3) simultaneously use 2 effective forms of birth control for at least 1 month before starting the drug, during the therapy, and for at least 3 years after discontinuing the therapy; and (4) receive counseling about the risk of birth control failure and risk of birth defects and abstain from every form of alcohol while taking the drug and for at least 2 months after the drug has been discontinued.
Monitoring. A careful history and physical examination is important to identify those at risk for or with a family history of hyperlipidemia; a medicine reconciliation is useful to note potential drug interactions. Monitoring parameters include complete metabolic and lipid panels at baseline, complete blood count with differential, and urinalysis. Lipids can be checked every 1 to 2 weeks once treatment is started until they stabilize, which is usually in 4 to 8 weeks, especially in patients with a personal or family history of hyperlipidemia. In those without a significant history of or baseline hyperlipidemia, checking the lipid panel each month for 3 to 6 months is recommended, especially to monitor for acute pancreatitis, which is rare. Triglyceride levels >600 mg/dL or cholesterol levels >300 mg/dL warrant a discontinuation of acitretin and close monitoring of lipids until they return to baseline. Sometimes, a fenofibrate is recommended for hypertriglyceridemia. Mild elevations in transaminases are rarely seen 2 to 8 weeks after the start of acitretin, but these are transient and just require monitoring. Checking the following laboratory values monthly for the first 3 to 6 months then every 3 months in cases of chronic acitretin therapy is recommended: complete blood count with differential, lipid and complete metabolic panels, and urinalysis. Common adverse reactions are xerostomia (dry mouth), cheilitis, alopecia, xerosis, and sunburn/sensitivity (especially if combined with phototherapy). Because elevated intracerebral pressure can also be an adverse event with acitretin, concomitant medications that have this adverse reaction (eg, tetracyclines) are contraindicated. Finally, because acitretin is a vitamin A derivative, any vitamin A supplementation should be avoided. Skeletal radiograph monitoring is not required.
After a full history and physical examination, reconciling additional medications is important because of potential interactions with various drugs, including all salicylates, nonsteroidal anti-inflammatory drugs, trimethoprim/sulfamethoxazole, sulfonamides, and tetracyclines, to name a few. Although it has oral, intramuscular, and intravenous routes of administration, oral administration is most common in the primary care setting. Methotrexate (MTX) should not be given to anyone planning to consume alcohol or women who are pregnant or lactating. Risks versus benefits should be discussed because of possible adverse effects; continuous monitoring is required with this drug. About 80% of patients with psoriasis who are treated with MTX respond usually within the first 4 weeks. In addition, for those couples planning on having a family, it is advised that men taking MTX should be off the drug for 3 months and women should discontinue for 1 menstrual cycle and have a negative pregnancy test at each visit.
Before starting a patient on MTX, a complete blood count with differential is required at baseline. This helps establish a baseline to follow for any possible MTX-induced pancytopenia. A complete metabolic panel will examine for poor renal function, low albumin, and liver function at baseline, the first 2 of which can be potential sources of pancytopenia because of increased levels of the free drug. In patients with renal disease, the dose of MTX can be adjusted according to the patient's creatinine clearance (as calculated using the Cockcroft-Gault formula). Testing for human immunodeficiency virus, tuberculosis, and hepatitis B and C is important before starting MTX because it is an immunosuppressive drug. Not only can MTX induce pancytopenia and hepatotoxcity, it can also cause pulmonary fibrosis. If pulmonary symptoms develop, a chest radiograph is warranted.
Once a patient is taking MTX, it is important to monitor for leukocytopenia or thrombocytopenia with a complete blood count with differential 7 to 14 days after starting or increasing the dose, every 2 to 4 weeks for the first few months, then every 1 to 3 months until stable. Leukocytopenia or thrombocytopenia are most likely to occur 7 to 10 days after initiating MTX and clinically serious cases can usually be corrected by 20 mg folinic acid (intravenous). Patients who are at highest risk of MTX-induced pancytopenia, and therefore require close monitoring, are those who have renal insufficiency, the elderly, those at risk for drug interactions or taking multiple medications, those with hypoalbuminemia, or those who are not taking folate. A basic metabolic panel for renal function is required every 2 to 3 months for patients taking MTX; for patients with impaired renal function, glomerular filtration rate needs to be calculated and monitored.
The newest guidelines divide those patients who are at low risk of developing hepatic fibrosis from those who are at highest risk. Patients are considered to have hepatic fibrosis risk factors if they have diabetes mellitus type 2, are obese, consume excess alcohol, have hepatitis B or hepatitis C virus, and/or are exposed to hepatotoxic drugs. In these patients pretreatment biopsies may be warranted and may be repeated after the patient has reached a 1.0-g total cumulative dose. Its important to obtain the blood sample at least 5 days after the last dose of MTX because the drug can erroneously elevate the results of liver function tests. Liver function tests showing minor elevations (less than twice the upper limit of normal) can be repeated in 2 to 4 weeks. Any abnormality (>3-fold the upper limit of normal) in liver function testing necessitates a temporary reduction of MTX and repeat of tests within 2 to 4 weeks. If there are persistent elevations in serum aspartate aminotranferase and hypoalbuminemia for 12 months, a liver biopsy should be considered before the patient reaches the 1.5- to 2.0-g cumulative dose mark. Whether MTX treatment should be initiated in high-risk patients or those with any of the risk factors for hepatic fibrosis should be decided on a case-by-case basis. If MTX is considered in these patients, a baseline liver biopsy is advisable; however, because some of these patients will discontinue MTX after 2 to 6 months because of adverse events or lack of efficacy, delaying a liver biopsy may also be advisable. Low-risk patients require a liver biopsy every time they reach the 1.5- to 2.0-g total cumulative dose. Recommendations to continue or discontinue MTX based on liver biopsy are based on the results of Roenigk et al. Whereas liver biopsy remains the gold standard, it is fraught with risk; a liver ultrasound (transient elastography) offers the ability to determine whether the liver is fibrosed, but studies can be limited, especially if the patient is overweight, has increased abdominal girth, or has a diagnosis of nonalcoholic steatohepatitis.
CsA is not contraindicated during pregnancy or lactation because it is a category C drug; however, it is contraindicated in patients with severe renal function, uncontrolled hypertension, and persistent malignancy. During a complete history the patient should be asked about anything that would increase their risk of nephrotoxcity, such as obesity, diabetes mellitus, advanced age, and concomitant use of nephrotoxic drugs. Exercise caution when dealing with patients taking multiple drugs because CsA has numerous drug-drug interactions due to its metabolism by the cytochrome p450 34A system or when administering with foods like grapefruit juice. During the complete physical examination at baseline and at each monthly visit, patients should be evaluated for skin neoplasms or infections because CsA increases the risk for developing squamous and basal cell carcinomas. In addition, at baseline, all patients initiating CsA should undergo routine age-appropriate cancer screening. Testing for tuberculosis and hepatitis C at baseline is advisable. Because CsA is immunosuppressive, vaccines may be helpful, and booster vaccination may be necessary; however, live vaccines are contraindicated with use of CsA.
Before starting a patient on CsA, 2 confirmed normal values for serum creatinine and blood pressure should be documented in addition to complete metabolic panels, including liver function testing, bilirubin, potassium, blood urea nitrogen, creatinine, complete blood counts, serum magnesium (which may decease while taking CsA), uric acid (which is relevant for those at risk for gout), and fasting serum lipids. Despite the recommendations on the package insert, the current consensus now requires monthly monitoring of renal function (creatinine clearance), blood pressure, physical examinations, adverse events, and a basic metabolic panel, including creatinine, blood urea nitrogen, potassium, complete blood count, and magnesium. It is recommended that the Modification of Diet in Renal Disease formula rather than the Cockcroft-Gault equation be used for overweight patients and those >50 years old. After checking fasting serum lipids at the initiation of therapy, these levels can be tested at least every 6 months for evidence of hypercholesterolemia or hypertriglyceridemia. Because of the monthly monitoring or laboratory tests and examinations, obtaining a CsA level is generally not necessary.
Treating patients for more than 1 to 2 years without nephrology consultation is not recommended because of CsA-associated risk of nephrotoxicity. Patients taking long-term therapy are also at risk of gingival hyperplasia, so yearly dental examinations are advised. The current recommendations for managing nephrotoxicity are reducing the dose of CsA by 25% to 50% (equivalent to 0.5 to 1.0 mg/kg/day) if serum creatinine levels increase more than 25% to 30% above baseline on 2 occasions (repeated measurements separated by 2 weeks). If serum creatinine fails to return to 10% of the patient's baseline after checking the levels every other week for 1 month, the dose of CsA should be reduced even further by 25% to 50%. Discontinuation of CsA should be considered if serum creatinine remains >10% above the patient's baseline.
For patients with no pre-existing hypertension but who developed hypertension while taking CsA as measured on 2 separate occasions, the PCP can either reduce the dose of CsA by 25% to 50% or treat the hypertension with a calcium channel blocker. For patients with existing hypertension, it is important to closely monitor blood pressure, serum creatinine, compliance, medications, diet, lifestyle, and drug interactions. For example, patients taking angiotensin-converting enzyme inhibitors will need to discontinue and replace them with either calcium channel blockers or β-blockers. Dihydropyridine calcium channel blockers (eg, isradipine and amplodipine) are more effective in reducing blood pressure and they can induce renal arteriolar vasodilation to contrast the vasoconstrictive effects of CsA. Verapamil, diltiazem, and nicardipine can increase the levels of CsA in the blood; nifedipine can cause gingival hyperplasia and should be avoided. Because of their ability to spare potassium and potentiate hyperkalemia with CsA, angiotensin-converting enzyme inhibitors and potassium-sparing diuretics should be avoided. β-Blockers can be used.
Systemic Treatments
Systemic treatments used to treat psoriasis are summarized in Table 5.
Biological Drugs (SORT Criteria Recommendation A, Level of Evidence 1)
Screening Before Administration of Biologic Therapy. Before starting a patient on any biologic drug, much needs to be assessed by a history and physical examination, laboratory tests have to be analyzed (see Table 6 and Table 7), and a closer follow-up must be considered. Though mostly well tolerated without significant side effects and because of the extensive follow-up required with their use, many PCPs will use biologics, working in conjunction with dermatologists who are familiar with their use. Drug allergies and current medications (dermatological and others) should be assessed, looking for those medicines that may increase immunosuppression or may exacerbate the psoriasis. In addition, a patient's medical history should be carefully evaluated and medicine regime reconciled to ensure that if the patient were to start taking a biologic drug, there would be as few interactions as possible. For example, reports of hypoglycemia in patients taking etanercept warrant a reduction of antidiabetic dosing and monitoring of glucose logs by PCPs for some of these patients. Because some patients who have plaque psoriasis have untreated antistreptolysin O titers from guttate psoriasis (that developed into plaque psoriasis), it always is a good idea to check an antistreptolysin O titer for every patient with new psoriasis.
Vaccines. Since patients taking these therapies may not receive live or live-attenuated vaccines (measles, mumps, rubella; oral polio vaccine; varicella zoster vaccine [VZV]; Bacillus Calmette-Guérin; yellow fever; and influenza [nasal]), ensuring that these patients are up to date with their age-appropriate vaccines is important. Annual inactivated influenza and pneumococcal (at least one dose, if necessary) vaccines should be given since these biologic drugs can lower the immune system's ability to fight infection. Vaccination for hepatitis A and B also are recommended before beginning a biologic. It usually takes 2 to 6 weeks for the body to produce a significant amount of antibodies after immunization.
Other Risks. Lymphoma and Leukemia: Lupus-like symptoms (butterfly sun-sensitive rash, oral ulcers, etc.) can be a side effect of using tumor necrosis factor (TNF)-α inhibitors. Some biological drugs also increase antinuclear antibody titers, so establishing a baseline antinuclear antibody titer is optional. Biological drugs can also increase the risk of cancer, mostly lymphoma and leukemia; however, it is uncertain whether it is the psoriasis or the initiation TNF-α blocking treatment that is the causative factor. According to some studies, many of the original clinical trials conducted using adalimumab and etanercept in patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, and psoriasis showed a 3-fold higher rate of lymphoma compared with the general US population. However, when meta-analyses of these randomized controlled trials were considered, most of the patients who populated the original trials were from cohorts with rheumatoid arthritis and Crohn's disease, which usually combined biological therapies with additional immunosuppressive agents, therefore introducing selection bias and confounding. In the absence of TNF-α blocking therapy, patients with moderate to severe rheumatoid arthritis, for example, have a 5- to 25-fold increased risk of developing lymphoma. It is therefore unclear whether the increases in the rate of lymphoma observed in these trials were related to TNF-α blocking therapy.
Congestive Heart Failure/Cardiac Events: Because signs and symptoms of congestive heart failure can worsen while taking a biologic drug like a TNF-α inhibitor, physicians should monitor these patients carefully and weigh the risk-to-benefit ratio. Major adverse cardiovascular events have been seen with the use of interleukin-12/23 inhibitors, namely briakinumab, which was pulled from clinical trials. Ustekinumab data also show some events, but further research is needed to clarify the role that these drugs may play in risk of major adverse cardiovascular events and the mechanism by which they may occur. The rate of major adverse cardiac events in patients taking ustekinumab was no greater than rates in both the general population and a population with psoriasis. Ustekinumab can cause reversible posterior leukoencephalopathy syndrome, which presents as a persistent headache, seizures, sudden vision changes, and mental and mood changes, so establishing a neurological history and physical examination at baseline is important.
Reactivation of Varicella Zoster
While the risk of potential reactivation of VZV is very low when a patient is taking a biologic drug, the risk increases when this patient is also taking oral prednisone for a comorbidity. Reactivation of VZV can lead to a potentially serious neurological complication, and VZV vasculopathies in immunocompromised patients have been described in the literature. In these cases the patient should be closely monitored for and educated about any signs or symptoms of stroke or transient ischemic attack and administration of VZV intravenous immunoglobulin should be considered.
Basic Pharmacology of Biologicals. The half-life of etanercept is 4 days, that of adalimumab is 10 to 20 days, infliximab is 8 to 9.5 days, and ustekinumab is 14.9 to 45.6 days; the time required for any of these drugs to be removed from the body once they are discontinued is approximately 4 to 5 half-lives. Once a patient begins taking a biologic drug, its important to closely follow them for drug-related adverse events. Reasons to stop a biologic drug are serious infection; severe persistent neurological symptoms such as headache, eye pain, loss of vision in one eye, or numbness; Guillain-Barré syndrome; lymph node swelling; unintended weight loss; malaise; easy bruising; bleeding; pallor; or serious allergic reaction such as anaphylaxis or angioedema.
Indications and Dosing. Because of the significant cost of biologics, more traditional medications should be tried first, if possible, and biologics used only when those fail or there is a contraindication to oral systemic therapy.
Acitretin (SORT Criteria Recommendation A, Level of Evidence 1)
This drug should be completely avoided in women of childbearing age because it is teratogenic and category X. Although acitretin may take 2 months to be eliminated from the body, when alcohol is consumed, eretinate, its metabolite, can have a half-life of up to 168 days. It is recommended that women abstain from consuming alcohol in any form while taking the drug and for at least 2 months after it is discontinued because the amount of metabolite is directly proportional to the amount of alcohol ingested. In fact, the teratogenic effects can occur for up to 2 to 3 years after acitretin discontinued in a patient who has consumed alcohol. Because of this, it is advised that if prescribing this for women of childbearing age, they must (1) have 2 negative urine or serum pregnancy tests before receiving their first dose of acitretin; (2) have monthly pregnancy tests before receiving their acitretin prescriptions; (3) simultaneously use 2 effective forms of birth control for at least 1 month before starting the drug, during the therapy, and for at least 3 years after discontinuing the therapy; and (4) receive counseling about the risk of birth control failure and risk of birth defects and abstain from every form of alcohol while taking the drug and for at least 2 months after the drug has been discontinued.
Monitoring. A careful history and physical examination is important to identify those at risk for or with a family history of hyperlipidemia; a medicine reconciliation is useful to note potential drug interactions. Monitoring parameters include complete metabolic and lipid panels at baseline, complete blood count with differential, and urinalysis. Lipids can be checked every 1 to 2 weeks once treatment is started until they stabilize, which is usually in 4 to 8 weeks, especially in patients with a personal or family history of hyperlipidemia. In those without a significant history of or baseline hyperlipidemia, checking the lipid panel each month for 3 to 6 months is recommended, especially to monitor for acute pancreatitis, which is rare. Triglyceride levels >600 mg/dL or cholesterol levels >300 mg/dL warrant a discontinuation of acitretin and close monitoring of lipids until they return to baseline. Sometimes, a fenofibrate is recommended for hypertriglyceridemia. Mild elevations in transaminases are rarely seen 2 to 8 weeks after the start of acitretin, but these are transient and just require monitoring. Checking the following laboratory values monthly for the first 3 to 6 months then every 3 months in cases of chronic acitretin therapy is recommended: complete blood count with differential, lipid and complete metabolic panels, and urinalysis. Common adverse reactions are xerostomia (dry mouth), cheilitis, alopecia, xerosis, and sunburn/sensitivity (especially if combined with phototherapy). Because elevated intracerebral pressure can also be an adverse event with acitretin, concomitant medications that have this adverse reaction (eg, tetracyclines) are contraindicated. Finally, because acitretin is a vitamin A derivative, any vitamin A supplementation should be avoided. Skeletal radiograph monitoring is not required.
Methotrexate (SORT Criteria Recommendation A, Level of Evidence 1)
After a full history and physical examination, reconciling additional medications is important because of potential interactions with various drugs, including all salicylates, nonsteroidal anti-inflammatory drugs, trimethoprim/sulfamethoxazole, sulfonamides, and tetracyclines, to name a few. Although it has oral, intramuscular, and intravenous routes of administration, oral administration is most common in the primary care setting. Methotrexate (MTX) should not be given to anyone planning to consume alcohol or women who are pregnant or lactating. Risks versus benefits should be discussed because of possible adverse effects; continuous monitoring is required with this drug. About 80% of patients with psoriasis who are treated with MTX respond usually within the first 4 weeks. In addition, for those couples planning on having a family, it is advised that men taking MTX should be off the drug for 3 months and women should discontinue for 1 menstrual cycle and have a negative pregnancy test at each visit.
Monitoring
Before starting a patient on MTX, a complete blood count with differential is required at baseline. This helps establish a baseline to follow for any possible MTX-induced pancytopenia. A complete metabolic panel will examine for poor renal function, low albumin, and liver function at baseline, the first 2 of which can be potential sources of pancytopenia because of increased levels of the free drug. In patients with renal disease, the dose of MTX can be adjusted according to the patient's creatinine clearance (as calculated using the Cockcroft-Gault formula). Testing for human immunodeficiency virus, tuberculosis, and hepatitis B and C is important before starting MTX because it is an immunosuppressive drug. Not only can MTX induce pancytopenia and hepatotoxcity, it can also cause pulmonary fibrosis. If pulmonary symptoms develop, a chest radiograph is warranted.
Once a patient is taking MTX, it is important to monitor for leukocytopenia or thrombocytopenia with a complete blood count with differential 7 to 14 days after starting or increasing the dose, every 2 to 4 weeks for the first few months, then every 1 to 3 months until stable. Leukocytopenia or thrombocytopenia are most likely to occur 7 to 10 days after initiating MTX and clinically serious cases can usually be corrected by 20 mg folinic acid (intravenous). Patients who are at highest risk of MTX-induced pancytopenia, and therefore require close monitoring, are those who have renal insufficiency, the elderly, those at risk for drug interactions or taking multiple medications, those with hypoalbuminemia, or those who are not taking folate. A basic metabolic panel for renal function is required every 2 to 3 months for patients taking MTX; for patients with impaired renal function, glomerular filtration rate needs to be calculated and monitored.
The newest guidelines divide those patients who are at low risk of developing hepatic fibrosis from those who are at highest risk. Patients are considered to have hepatic fibrosis risk factors if they have diabetes mellitus type 2, are obese, consume excess alcohol, have hepatitis B or hepatitis C virus, and/or are exposed to hepatotoxic drugs. In these patients pretreatment biopsies may be warranted and may be repeated after the patient has reached a 1.0-g total cumulative dose. Its important to obtain the blood sample at least 5 days after the last dose of MTX because the drug can erroneously elevate the results of liver function tests. Liver function tests showing minor elevations (less than twice the upper limit of normal) can be repeated in 2 to 4 weeks. Any abnormality (>3-fold the upper limit of normal) in liver function testing necessitates a temporary reduction of MTX and repeat of tests within 2 to 4 weeks. If there are persistent elevations in serum aspartate aminotranferase and hypoalbuminemia for 12 months, a liver biopsy should be considered before the patient reaches the 1.5- to 2.0-g cumulative dose mark. Whether MTX treatment should be initiated in high-risk patients or those with any of the risk factors for hepatic fibrosis should be decided on a case-by-case basis. If MTX is considered in these patients, a baseline liver biopsy is advisable; however, because some of these patients will discontinue MTX after 2 to 6 months because of adverse events or lack of efficacy, delaying a liver biopsy may also be advisable. Low-risk patients require a liver biopsy every time they reach the 1.5- to 2.0-g total cumulative dose. Recommendations to continue or discontinue MTX based on liver biopsy are based on the results of Roenigk et al. Whereas liver biopsy remains the gold standard, it is fraught with risk; a liver ultrasound (transient elastography) offers the ability to determine whether the liver is fibrosed, but studies can be limited, especially if the patient is overweight, has increased abdominal girth, or has a diagnosis of nonalcoholic steatohepatitis.
Cyclosporine (SORT Criteria Recommendation A, Level of Evidence 2)
CsA is not contraindicated during pregnancy or lactation because it is a category C drug; however, it is contraindicated in patients with severe renal function, uncontrolled hypertension, and persistent malignancy. During a complete history the patient should be asked about anything that would increase their risk of nephrotoxcity, such as obesity, diabetes mellitus, advanced age, and concomitant use of nephrotoxic drugs. Exercise caution when dealing with patients taking multiple drugs because CsA has numerous drug-drug interactions due to its metabolism by the cytochrome p450 34A system or when administering with foods like grapefruit juice. During the complete physical examination at baseline and at each monthly visit, patients should be evaluated for skin neoplasms or infections because CsA increases the risk for developing squamous and basal cell carcinomas. In addition, at baseline, all patients initiating CsA should undergo routine age-appropriate cancer screening. Testing for tuberculosis and hepatitis C at baseline is advisable. Because CsA is immunosuppressive, vaccines may be helpful, and booster vaccination may be necessary; however, live vaccines are contraindicated with use of CsA.
Monitoring
Before starting a patient on CsA, 2 confirmed normal values for serum creatinine and blood pressure should be documented in addition to complete metabolic panels, including liver function testing, bilirubin, potassium, blood urea nitrogen, creatinine, complete blood counts, serum magnesium (which may decease while taking CsA), uric acid (which is relevant for those at risk for gout), and fasting serum lipids. Despite the recommendations on the package insert, the current consensus now requires monthly monitoring of renal function (creatinine clearance), blood pressure, physical examinations, adverse events, and a basic metabolic panel, including creatinine, blood urea nitrogen, potassium, complete blood count, and magnesium. It is recommended that the Modification of Diet in Renal Disease formula rather than the Cockcroft-Gault equation be used for overweight patients and those >50 years old. After checking fasting serum lipids at the initiation of therapy, these levels can be tested at least every 6 months for evidence of hypercholesterolemia or hypertriglyceridemia. Because of the monthly monitoring or laboratory tests and examinations, obtaining a CsA level is generally not necessary.
Treating patients for more than 1 to 2 years without nephrology consultation is not recommended because of CsA-associated risk of nephrotoxicity. Patients taking long-term therapy are also at risk of gingival hyperplasia, so yearly dental examinations are advised. The current recommendations for managing nephrotoxicity are reducing the dose of CsA by 25% to 50% (equivalent to 0.5 to 1.0 mg/kg/day) if serum creatinine levels increase more than 25% to 30% above baseline on 2 occasions (repeated measurements separated by 2 weeks). If serum creatinine fails to return to 10% of the patient's baseline after checking the levels every other week for 1 month, the dose of CsA should be reduced even further by 25% to 50%. Discontinuation of CsA should be considered if serum creatinine remains >10% above the patient's baseline.
For patients with no pre-existing hypertension but who developed hypertension while taking CsA as measured on 2 separate occasions, the PCP can either reduce the dose of CsA by 25% to 50% or treat the hypertension with a calcium channel blocker. For patients with existing hypertension, it is important to closely monitor blood pressure, serum creatinine, compliance, medications, diet, lifestyle, and drug interactions. For example, patients taking angiotensin-converting enzyme inhibitors will need to discontinue and replace them with either calcium channel blockers or β-blockers. Dihydropyridine calcium channel blockers (eg, isradipine and amplodipine) are more effective in reducing blood pressure and they can induce renal arteriolar vasodilation to contrast the vasoconstrictive effects of CsA. Verapamil, diltiazem, and nicardipine can increase the levels of CsA in the blood; nifedipine can cause gingival hyperplasia and should be avoided. Because of their ability to spare potassium and potentiate hyperkalemia with CsA, angiotensin-converting enzyme inhibitors and potassium-sparing diuretics should be avoided. β-Blockers can be used.
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