Summary. Anecdotal experience with full blood count (FBC) technology incorporating analysis of depolarized laser light (DLL) for the enumeration of eosinophils showed that malaria infection generated unusual distributions in the white cell channels. The objective of this study was to identify and define criteria for a diagnosis of malaria using this technology. To determine sensitivity, specificity, and positive and negative predictive values, 224 directed samples referred specifically for malaria were used; true positives were defined as those in which malaria was identified by microscopic and/or immunological methods. For the DLL method, positive was defined as one or more large mononuclear cell(s) for which the 90Њ depolarized signal exceeded the 90Њ polarized signal. To determine possible utility in a routine haematology laboratory setting, 220 random undirected FBC samples were evaluated for possible malaria infection by the DLL method. Of the 224 directed samples, 95 were malaria positive as determined by microscopic and/or immunological methods, and 129 were negative. For the DLL method, overall sensitivity was 72% (90% in the case of Black Africans), and specificity 96%. Positive and negative predictive values overall were 93% and 82% respectively. In the utility study a single positive result was identified among the 220 samples studied. This was found to be from a patient with malaria. The detection of unexpected malaria by automated screening FBC analysis could substantially lower the mortality and morbidity from unascertained infection, especially in indigenous African peoples.

Objectives: To investigate IgG, IgM, and IgA, antiphospholipid antibodies (aPL), against cardiolipin (aCL), b 2 -glycoprotein I (anti-b 2 GPI), and prothrombin (anti-PT), in black South African patients with infectious disease. Unlike patients with systemic lupus erythematosus (SLE) and the antiphospholipid syndrome (APS), raised levels of aPL in infectious diseases are not usually associated with thrombotic complications. Patients and methods: Serum samples from 272 patients with a variety of infectious diseases (100 HIV positive, 112 leprosy, 25 syphilis, 25 malaria, and 10 HCV patients) were studied and compared with autoantibody levels in 100 normal controls. All three aPL were measured using commercial enzyme linked immunosorbent assay (ELISA) kits. Results: Raised levels of all thee aPL were found in all patient groups studied: aCL in 7%, anti-b 2 GPI in 6%, and aPT in 43% of 100 HIV patients, in 29%, 89%, and 21% of 112 patients with leprosy, in 8%, 8%, and 28% of 25 patients with syphilis, in 12%, 8%, and 28% of 25 patients with malaria, and in 20%, 30%, and 30% of 10 HCV patients studied, respectively. Conclusions: The prevalence of aCL and anti-b 2 GPI in black South African HIV positive patients, or those with syphilis, malaria, or hepatitis C virus is lower than reported for mixed race or white populations. aPT were the most prevalent aPL detected in these patient groups, except in patients with leprosy, for whom anti-b 2 GPI was the most prevalent, and where the spectrum of aPL was similar to that seen in patients with SLE and APS.

A 57-year-old woman with a history of transient ischaemic attacks and six recurrent foetal losses accompanied by elevations of antiphospholipid antibodies was diagnosed as having a "primary" antiphospholipid syndrome. She was followed up for 5 years, and she developed anaemia, leucopenia and splenomegaly. A bone marrow trephine was diagnostic of Waldenstrom's macroglobulinaemia. A false positive serological test for syphilis was demonstrated and apparently had been noted in her second pregnancy more than 20 years prior to her presentation with an antiphospholipid syndrome. There had previously been no indication to perform serum electrophoretic studies. This case illustrates the importance of this investigation in any middle-aged patient presenting with an antiphospholipid syndrome and a monoclonal gammopathy This finding might presage the development of a more serious condition, even years later (as in our patient).