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, particularly in high-prevalence regions, sarcoidosis is frequently misdiagnosed as TB. Objective. To review the clinical features of sarcoidosis patients in an SApopulation, 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 lymphnodes, 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%

HLA class I and class II antigens in sarcoidosis

Background. Sarcoidosis is a multisystem granulomatous disorder. Its exact cause is unknown, but it is believed that an external agent may cause the characteristic immune reaction in genetically susceptible individuals. There is therefore general recognition that genetic vulnerability to sarcoidosis is one of the potential risk factors. HLA is encoded by genes in the major histocompatibility complex on chromosome 6. These surface cells are important in presentation of antigen and play a key part in the body’s immune response to external antigens. Various HLA subtypes are more common in people with sarcoidosis than in those without. Variances in vulnerability, presentation, progression and prognosis have been related to different HLA phenotypes. HLA genes offer information into the factors driving sarcoidosis and prognosticating tools. However, in Africa, including South Africa (SA), there are no data on HLA types in relation to sarcoidosis. Objectives. To determine HLA class I and II associations in SA sarcoidosis patients. Methods. Phenotype frequencies of HLA-A, B and C and DQB1 and DRB1 were calculated for 51 consecutive patients with biopsy-proven sarcoidosis attending the respiratory clinic at Charlotte Maxeke Johannesburg Academic Hospital and 63 controls, who were potential organ donors. The frequencies of the tested HLA loci were determined by direct counting. The significance of the associations between the various loci tested for and the presence or absence of sarcoidosis was estimated from 2 × 2 tables using the χ2 test. Results. Of the 51 patients, 70.6% were female. The mean age was 44.6 years. Analysis of HLA class I and class II phenotypes in sarcoidosis patients revealed a significant association with HLA-B15, C4, C7, C12, C15, C16, C17, DQ3, DR8 and DR11. In addition, a significant negative (protective) association with HLA A9, A28, B12, B17 and DR2 was observed. Conclusion. This HLA study in SA patients suggests that genetic factors play a role in the causation of sarcoidosis. Some HLA subtypes have a significant association with sarcoidosis in SA patients, while other subtypes may be protective. The study supported the association of HLA antigens with sarcoidosis and implies that there is a genetic predisposition to sarcoidosis in the SA population

Inflammatory Pseudotumour of the Lung: A Case Report and Literature Review

We describe a patient with inflammatory pseudotumour of the lung. He was a young man who presented with haemotysis and the chest X-ray and computerized tomography were indicative of a nonbenign lesion in the right upper lobe. Excision biopsy confirmed the diagnosis of inflammatory myofibroblastic pseudotumour of the lung. This is a rare inflammatory nonneoplastic condition commonly affecting children and young adults

The Effective Mutation Rate at Y Chromosome Short Tandem Repeats, with Application to Human Population-Divergence Time

We estimate an effective mutation rate at an average Y chromosome short-tandem repeat locus as 6.9×10(-4) per 25 years, with a standard deviation across loci of 5.7×10(-4), using data on microsatellite variation within Y chromosome haplogroups defined by unique-event polymorphisms in populations with documented short-term histories, as well as comparative data on worldwide populations at both the Y chromosome and various autosomal loci. This value is used to estimate the times of the African Bantu expansion, the divergence of Polynesian populations (the Maoris, Cook Islanders, and Samoans), and the origin of Gypsy populations from Bulgaria