Browsing by Author "Van de Wal, B. W."

Now showing 1 - 7 of 7
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    Cost-benefit of medicines - indapamide compared with other thiazide diuretics
    (Health & Medical Publishing Group, 1994) Van de Wal, B. W.
    [No abstract available]
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    Early bactericidal activity of ethambutol, pyrazinamide and the fixed combination of isoniazid, rifampicin and pyrazinamide (Rifater) in patients with pulmonary tuberculosis
    (Health & Medical Publishing Group, 1996) Botha, F. J. H.; Sirgel, F. A.; Parkin, D. P.; Van de Wal, B. W.; Donald, P. R.; Mitchison, D. A.
    The early bactericidal activity (EBA) of ethambutol, pyrazinamide and the fixed combination of isoniazid, rifampicin and pyrazinamide (Rifater: Mer National) was evaluated in patients with pulmonary tuberculosis who were sputum-positive on microscopy for acid-fast bacilli. Twenty-eight patients (mean age 33 years and weight 51 kg on average; range 40-59 kg) were studied. The fall in viable counts of Mycobacterium tuberculosis in sputum collections during the 2 days following the start of treatment was estimated from counts of colony-forming units (CFUs) of M. tuberculosis per ml of sputum cultured on selective 7H10 agar medium. The EBA for ethambutol determined in 9 patients was 0.245 ± 0.046, log10 CFU/ml sputum/day, that for pyrazinamide was 0.003 ± 0.014 log10 CFU/ml sputum/day and that for Rifater 0.558 ± 0.054 log10 CFU/ml sputum/day. The results obtained are similar to those reported in a previous study of the first 2 days of treatment, but in smaller numbers of patients, and confirm the moderate EBA of ethambutol while pyrazinamide is again shown to have very little EBA. Rifater has a marked EBA which may be due mainly to the action of isoniazid. This methodology may be valuable in the rapid evaluation of the bactericidal activity of new antituberculosis agents and the comparison of different dose sizes of agents of the same class.
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    HIV-associated nephropathy - an initial presentation in an HIV-positive patient
    (Health & Medical Publishing Group, 1994) Bates, W. D.; Muller, N.; Van de Wal, B. W.; Jacobs, J. C.
    The lesions of HIV-associated nephropathy occur in patients with AIDS, AIDS-related complex and in individuals clinically asymptomatic for HIV infection. We report on a 35-year-old black South African woman who presented with nephrotic syndrome and renal failure. The renal biopsy appearance suggested HIV infection and this was subsequently verified. This finding emphasises the possibility that otherwise asymptomatic patients presenting with renal disease may be HIV-positive.
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    A nosocomial outbreak of Crimean-Congo haemorrhagic fever at Tygerberg Hospital. Part I. Clinical features
    (Health & Medical Publishing Group, 1985) Van Eeden, P. J.; Joubert, J. R.; Van de Wal, B. W.; King, J. B.; De Kock, Annamarie; Groenewald, J. H.
    Crimean-Congo haemorrhagic fever (CCHF) is a rare disease in South Africa. From 1981 to September 1984, 8 sporadic primary cases were reported. An outbreak of CCHF in a large university hospital is described; of 8 patients diagnosed 2 died (the index and a secondary case). Four patients were seriously ill and 2 had a mild illness. Problems were encountered in diagnosing the disease, which presents initially with influenza-like symptoms, differing only in severity from influenza. However, petechiae and other manifestations of a bleeding tendency distinguished it from influenza in the later phase of the disease. Special investigations, especially those revealing leucopenia and thrombocytopenia, were critically important in early diagnosis. The dilemma of handling this highly contagious disease is that definite virological diagnosis is time-consuming and is conducted in only one high-security laboratory 1600 km distant. A further case was admitted 3 months later from a different locality and confirmed virologically but no secondary cases could be confirmed or traced.
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    A nosocomial outbreak of Crimean-Congo haemorrhagic fever at Tygerberg Hospital. Part II. Management of patients
    (Health & Medical Publishing Group, 1985) Van Eeden, P. J.; Van Eeden, S. F.; Joubert, J. R.; King, J. B.; Van de Wal, B. W.; Michell, W. L.
    During the outbreak of Crimean-Congo haemorrhagic fever (CCHF) at Tygerberg Hospital 8 patients were diagnosed positive. CCHF was diagnosed in another patient several months later. The treatment of these 9 cases is outlined. When it became evident that CCHF could present with a spectrum of severity, treatment was adjusted according to each patient's requirements. The essential components consisted of correction of haematological abnormalities combined with hyperimmune serum; the latter is particularly important for the severely ill patient with no antibodies to CCHF. The antiviral agents ribavirin and interferon were used but evidence to substantiate their application in future cases was inconclusive. Interferon was discontinued because of severe side-effects, many of which simulated the clinical features of CCHF. Objective improvement after corticosteroid treatment was noted in only 1 patient, but some of her symptoms could have been due to a transfusion reaction. Antibiotics were not routinely used. The 2 patients who died were diagnosed late, did not receive hyperimmune serum, and eventually developed multi-organ failure. The course of CCHF can probably be modified if the diagnosis is made early, if antiserum is given, and if the haematological abnormalities are promptly corrected.
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    A nosocomial outbreak of Crimean-Congo haemorrhagic fever at Tygerberg Hospital. Part IV. Preventive and prophylactic measures
    (Health & Medical Publishing Group, 1985) Van de Wal, B. W.; Joubert, J. R.; Van Eeden, P. J.; King, J. B.
    During the Crimean-Congo haemorrhagic fever (CCHF) outbreak at Tygerberg Hospital a particular problem existed: a simultaneous influenza epidemic complicated the screening of contacts because of its very similar clinical picture to that of early CCHF. The methods of identifying and screening contacts are described. Of 459 listed CCHF contacts, 7 (1.5%) developed the disease; 6 were contacts of the index case and only 1 a contact of a secondary case. Two of the 7 CCHF patients had no direct contact with the index case; this caused a great concern about the dissemination, despite the otherwise full protective measures. Four of 46 blood contacts (8.7%) and 3 of 9 needle contacts (33%) developed the disease. Prophylactic interferon therapy had to be discontinued because of side-effects mimicking the symptoms of CCHF. Ribavirin was used prophylactically in 6 of the 9 inoculation contacts. One of the patients on ribavirin had a mild clinical course while 5 others who received the drug developed neither clinical CCHF nor antibodies to the virus. Two of the 3 needle contacts not treated with ribavirin had a severe clinical course. One contact with needle inoculation and 42 proven blood contacts who had not received ribavirin did not become infected. No firm conclusion can therefore be made about the protective value of prophylactic ribavirin.
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    'n Oorsig van die bepaling van die vroeë bakterisidiese aktiwiteit van verskeie antituberkilosemiddels
    (AOSIS, 2003) Donald, P. R.; Sirgel, F. A.; Venter, A.; Fourie, P. B.; Parkin, D. P.; Seifart, H. I.; Van de Wal, B. W.; Maritz, J. S.
    The early bactericidal activity (EBA) of an antituberculosis agent is the daily decline in log10 colony forming units of M tuberculosis per ml of sputum during the first two days of treatment with the agent. It reflects the capacity of an agent to kill the actively metabolising organisms in tuberculosis lung cavities. It offers a relatively cheap means to evaluate the antituberculosis activity of an agent in a small group of patients within a matter of months. This article summarizes the authors’ experience in seven published EBA studies and identifies sources of variation in the procedure. The patients who participated in these studies had a mean age of 33 years, a mean weight of 50 kg and there was extensive or massive involvement of the lungs in 55% of patients. The highest EBA values (0,50-0,66) were found in groups of patients receiving isoniazid and the lowest values (0,05 and 0,09 respectively), in patients receiving the aminoglycosides amikacin and paromomycin in a dose of 15 mg/kg body weight. The variation in EBA in 248 patients was 0,0312 and the variation ascribable to the process of sputum production and collection was 0,0233. This implies that the different aspects of sputum production and collection involved in obtaining a representative sputum sample are responsible for most of the variation in EBA results. The selection of patients for inclusion in EBA studies and their ability to co-operate in producing a representative sputum specimen are of critical importance in the successful completion of EBA studies.