Page 193 - The Vasculitides, Volume 1: General Considerations and Systemic Vasculitis

The Clinical Approach to Patients with Vasculitis 169

for prompt administration of high-dose corticosteroid therapy while awaiting tissue biopsy
results.

Medical Considerations Prior to
Immunosuppression

Specific treatment of the vasculitides is covered elsewhere in this book. As most
treatment regimens include corticosteroids alone or with concomitant immunosuppressive
medication, the greatest concern rests with the risk of infection. Therefore every effort should
be taken to exclude infection prior to initiation of such therapy including prophylaxis and
vaccination when appropriate. Two-thirds of patients receiving immunosuppressive
medications were asymptomatic at time of HBV reactivation [40]. The latter is preventable
with preemptive antiviral therapy in appropriately selected patients, particularly those with
HBs and core antigenemia, or present HBV DNA. Patients with suspected TB exposure
should be screened with a tuberculin skin test and interferon-gamma release assay (IGRA)
prior to initiation of corticosteroids and immunosuppressive therapy [41]. Such was also the
case in a small population of patients with TAK already receiving immunosuppressive
therapy [42]. Patients with AAV have higher rates of Pneumocystis jirovecii pneumonia
(PCP) compared to others with autoimmune disease on similar immunosuppressive regimens.
A meta-analysis of almost 12,000 patients with connective tissue disease found incident PCP
in 12% of GPA patients with a 63% mortality rate [43]. Corticosteroids and
cyclophosphamide use, and prolonged lymphopenia are known risk factors for PCP, however
unlike HIV; there are no guidelines for PCP prophylaxis in the vasculitides. Trimethoprim-
sulfamethoxazole (TMP-SMZ) is the commonest prophylactic agent administered at dosages
of 800/160 mg on alternate days and 400/80 mg daily. Prophylaxis with trimethoprim-
sulfamethoxazole should be considered for all AAV patients receiving cyclophosphamide.
The dose of TMP-SMZ should be adjusted for renal function. The cost-effectiveness of
pentamidine and atovaquone prophylaxis has not been assessed in patients intolerant to TMP-
SMZ. Vaccination is an important infection prevention strategy in the vasculitides however
there are yet disease-specific and medication-specific vaccination guidelines. The Centers for
Disease Control and Prevention (CDC) guidelines for immunocompromised individuals is
applicable to those taking immunosuppressive medication [44]. The live varicella,
measles/mumps/rubella, yellow fever, typhoid fever, polio, and intra-nasal attenuated
influenza, should be avoided in patients receiving greater than 20 mg/day of prednisone or
other immunosuppressive medications. In one retrospective analysis of a cohort of patients
with autoimmune disease on biologic therapy, non-biologic disease modifying anti-rheumatic
drugs, corticosteroids, and vaccination with the live herpes zoster vaccine were safely
administered even in the setting of immunosuppressive therapy [45]. The CDC recommends
that patients age >60 years taking 20 mg/day or less of prednisone, as well as methotrexate
and azathioprine at doses employed for rheumatic diseases, may safely receive the varicella
zoster virus vaccination without interruption in therapy compared to those receiving biologic
therapy. All patients should be offered inactive influenza vaccination annually.
The pneumococcal polysaccharide vaccination should be administered to adults less than 65
years of age. Patients older than 65 who have not previously received pneumococcal

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