Objectives Plasmablastic lymphoma (PBL) is a clinically aggressive lymphoma which has a predilection for extranodal sites and is frequently HIV‐associated. The incidence of non‐Hodgkin lymphoma is thought to be reduced by widescale antiretroviral therapy (ART) coverage, but the literature is sparse as regards the impact of ART on the incidence of PBL and its outcomes in South Africa (SA). This study aimed to compare factors of interest in cases of PBL diagnosed before and after the widespread availability of ART in Johannesburg, SA. Methods All cases of PBL diagnosed in the state sector hospitals of Johannesburg in 2007 and 2017 (before and after the widespread availability of ART, respectively) were extracted from the laboratory information system, and factors of interest compared. Results The majority (> 95%) of cases of PBL were seen among people with HIV infection (PWH) at both time‐points, and the proportion of patients on ART and with virological suppression (VS) increased significantly in 2017. However, the number of cases of PBL did not differ significantly between the two years assessed, comprising 46/397 (11.6%) and 53/582 (9.6%) of all lymphomas in 2007 and 2017, respectively (P = 0.23). Ongoing risk for PBL among PWH with virological control and immunological recovery was evident in 2017, as 18.9% of the patients had both VS and CD4 counts > 200 cells/μL at diagnosis. Inferior survival times were associated with elevated lactate dehydrogenase (LDH) levels and Epstein Barr virus (EBV) negativity, but were not influenced by the presence of AIDS, ART or VS. EBV negativity was significantly associated with VS, and appeared to flag a particularly aggressive form of the disease. Conclusions Widescale ART coverage has not reduced the incidence of PBL in Johannesburg, and an ongoing risk for this disease among PWH with adequate virological control and immunological recovery persists.

Background. The HIV epidemic in South Africa (SA) has had a substantial impact on laboratory services, at least partially owing to the well-described propensity to cytopenias in HIV-positive patients. Objectives. (i) To formally gauge the impact of HIV infection on the state sector haematology services in SA by determining the HIV seropositivity rate among full blood counts (FBCs) performed at a large academic state sector laboratory; and (ii) to document the prevalence of cytopenias among HIV-positive patients in this setting. Methods. Randomly selected FBCs submitted to the National Health Laboratory Service laboratory at Chris Hani Baragwanath Academic Hospital, Johannesburg, were extracted from the laboratory information system (LIS) and retrospectively reviewed. HIV test results and other pertinent information in the LIS were documented, as was the presence of any cytopenias. Results. HIV status was documented in 561 of 1 006 samples (55.8%), with 307 (54.7%) of these being HIV-positive. Of the HIV-positive patients, 63.2% had one or more cytopenia/s. Anaemia was present in 183/307 (59.6%) of the HIV-positive patients, and was severe (haemoglobin <8 g/dL) in 32/307 (10.4%). Multivariate linear regression analysis showed significant independent associations between the presence of anaemia and both immunological AIDS (iAIDS) (p<0.0001) and male sex (p<0.025), but not HIV viral load (VL) (p=0.33) or antiretroviral therapy (ART) exposure (p=0.70). Thrombocytopenia and neutropenia were present in 37/307 (12.1%) and 11/51 (21.6%) of the HIV-positive patients, respectively, with no statistically significant association between either of these cytopenias and iAIDS, exposure to ART or VL. Conclusions. The findings reflect the substantial impact of the HIV epidemic on state sector laboratory resources, particularly the haematology service.

Background. Causes of thrombocytopenia range from laboratory errors to life-threatening pathological conditions. To establish the cause, appropriate laboratory investigation is required. Objectives. To determine the prevalence and causes of platelet counts <100 × 10 9 /L in state health facilities in Johannesburg, South Africa, as well as the quality of the subsequent laboratory work-up in this setting. Methods. Full blood counts (FBCs) performed on 7 randomly selected days at the National Health Laboratory Service laboratory at Chris Hani Baragwanath Academic Hospital were retrospectively reviewed. Samples with platelet counts <100 × 10 9 /L were identified, and pertinent information was extracted from the laboratory database. Results. Of 4 456 FBCs included, 381 (8.6%) had a platelet count of <100 × 10 9 /L. Thrombocytopenia prevalence rates were high in haematology/oncology wards (34.4%), intensive care units (20.5%) and medical wards (18.7%) and among neonatal inpatients (16.5%), and were lowest in outpatient clinics (1-2%). A cause was apparent in ~60% of patients, the commonest causes being chemotherapy and sepsis (each comprising >20% of the recognised causes). Spurious thrombocytopenia, disseminated tuberculosis, aplastic anaemia, immune thrombocytopenia and malignant marrow infiltration each accounted for 5-10% of the causes, while malaria, thrombotic thrombocytopenic purpura, HIV effect and liver disease were each identified in <5% of cases. HIV status was documented in ~70% of the patients, of whom ~50% tested positive. The quality of the laboratory work-up showed differences between specialties within the hospital setting, and was poorest in the primary healthcare clinic sector. Conclusion. Thrombocytopenia is common in hospitalised patients in the Johannesburg academic state sector. Differences in the quality of the laboratory work-up emphasise the need for a standardised approach to thrombocytopenia investigation and increased awareness among clinicians.