Sarcoidosis in Johannesburg, South Africa: A retrospective study.

Background: Sarcoidosis is a multisystem granulomatous condition of uncertain aetiology that most frequently affects the lungs. Because of clinical and radiological similarities with tuberculosis (TB), particularly in high-prevalence regions, sarcoidosis is frequently misdiagnosed as TB. Objectives: To review the clinical features of sarcoidosis patients in a South African (SA) population, adding clinical information to the relatively few studies that have been conducted in SA patients with sarcoidosis. Methods: This was a retrospective study of 102 sarcoidosis patients conducted between 2002 and 2006 at the Charlotte Maxeke Johannesburg Academic Hospital. Results: Of 102 sarcoidosis patients, there were 69 (67.6%) females and 33 (32.4%) males. The majority (85.3%) were non-smokers. The mean age of the group was 44.6 years. One-third of patients had chronic comorbid diseases. Almost 17% had been treated initially for TB, prior to being diagnosed as having sarcoidosis. Two patients developed active TB while receiving corticosteroid treatment for sarcoidosis. The salient clinical manifestations were dry cough (the most common presenting symptom in 82.4%), dyspnoea in 53.9%, cutaneous lesions other than erythema nodosum in 33.3%, and on lung examination crackles were noted in 37.3% of patients. Raised angiotensin-converting enzyme (ACE) levels were found in 56.8% of patients. The majority (48%) of patients had stage II chest radiographic changes. Cutaneous (28.4%), mediastinal lymph node (25.5%) and transbronchial lung (25.5%) biopsies were the most frequent sites confirming granulomatous inflammation. Overall, 21.2% of patients had obstructive airway disease. Systemic corticosteroids were indicated in 87.3% of patients and the relapse rate was 60.7%. Conclusion: Sarcoidosis is often initially misdiagnosed as TB in SA. The most common biopsy sites for histological confirmation were the skin and mediastinal lymph nodes, and transbronchial lung biopsies were also frequently taken. Stage II chest radiographic changes were most common. Overall, systemic corticosteroids were administered in 87.3% of cases and the relapse rate was 60.7%.