| Summary: | A dissertation submitted to the Faculty of Medicine,
Universlty of the Witwatersrand,
in partial fulfilment of the requirements for
the degree of Master of Medicine in the branch of Haematology. === Despite the efforts, for more than twenty years, to control malaria, the incidence of this
disease still appears to be escalating globally. At the Chris Hani/Baragwanath Hospital,
data analysis of malaria admissions between January 1994 to December 1996 showed an
increasing trend from year to year.
The main objective of the study was to try and provide some insight into this increasing
rate of malaria at the ChrisHani/Baragwanath Hospital. The study was structured into
two main parts: a retrospective analysis which concentrated on malaria admissions
between and including January 1994 and March 1994, and a prospective analysis
interviewing and examining all the malaria cases that were diagnosed between and
including January 1995 and March 1995. Both aspects of the study assessed the patients
socioeconomically, haematologically and immunologically. A detailed travel,medical and
drug history was taken through the aid of a questionnaire.
Two hundred and sixty-three patients (175 male and 88 female), of which 35% (91/263)
were children (< 13 years old), were diagnosed with malaria. The clinical and
laboratory presentations were consistent with other studies. The prevalence of
complicated disease however was less than what has been described in the literature;
cerebral malaria (as defined by Warrell, 1982) was documented in 1% of patients,
hypoglycaemia (glucose < 2.2 mmol/l) and renal failure (creatinine > 265 umol/l)
accounted for 5% and 3% of the cases respectively. In contrast to this 32% had
features of liver dysfunction, however it appeared that haemolysis was the main
contributing factor to the liver derangement. The most common infecting species was
Plasmodium falciparum, alone (91.3% of the patients) or part of a mixed infection
with either P. vivax or P.ovale (3.8% of patients). More than 88% of the infections were
contracted in other African, mainly southern African countries, the most important of
which was neighbouring Mozambique (58%). About 11% were contracted in endemic
areas of South Africa i.e Northern Province, Mpumalanga and Kwazulu Natal. Twelve
percent of cases (24/203) gave a history of previous malaria, The underlying immune
status of these patients was analyzed using the Indirect Fluorescence Antibody Test
(IFAT) and compared with the total study group. The test did not reveal any striking
differences between the two groups. The previously exposed patients however did
demonstrate a much lower parasitaemia, with 71% (17/24) of cases presenting with a
parasite density <_;1%. These results may indicate the ability of these patients to clear
their parasitaemias earlier due to previous sensitization, with the subsequent
establishment of a low grade chronic infection.
Seven of 88 women admitted had a documented pregnancy at the time of diagnosis.
Foetal death was recorded in 517 cases which confirms the poor prognosis in pregnancy
associated malaria infection, reported by other authors.
Fifteen patients (13 adults and 2 children) required admission into the intensive care unit.
Indications included high parasite loads, > 5% (67%) and renal failure,
creatinine> 265 umol/l (33%).
Standard chemotherapy was administered to all the patients with the most frequently
used being quinine (94% of cases), alone or in combination with other drugs. The use of
prophylactic agents for the prevention ofmalaria was restricted to twelve patients (8%),
with the majority of individuals being ignorant about( malaria and therefore being
unaware that any medication along with other preventative measures, were necessary
prior to entering , and while staying in an endemic region. It was also apparent that the
correct dosage was not adhered to as none of the patients completed their antimalarial
course after returning from the malaria area. The most commonly used prophylactic
drugs were chloroquine, alone or in combination with proguanil and pyrimethamine plus
dapsone (Maloprim), The latter is no longer recommended routinely as a prophylactic
agent.
Following univariate analysis using Fisher's exact test and the student t-test, and a
multivariate: nalysis (using a logistic regression model), hyperparasitaemia (p=O.0070)
and renal failure (p=O.0016) were identified as significant predictors of poor outcome.
Significant differences were also demonstrated in the mean WCC and the mean HB
levels between the survivors versus the patients that died, indicating that a significantly
elevated WCC and an anaemia at presentation, may be important risk factors towards
the establishment of severe/complicated infection. The overall mortality rate was 3%.
Climatic data (which was limited to the Johannesburg area), together with evidence that
the malaria bearing Anopheles vector does not exist in Gauteng suggests that the
conditions in the city may not be suitable for local transmission of malaria during the
summer. It therefore appears that all efforts need to be channeled into the education of
our travelers who visit malaria endemic regions and upon returning succumb to
'imported' malaria. Perhaps the education of the traveler alone is not sufficient, and
medical personnel who diagnose the condition and who prescribe prophylactic agents
need to revise their knowledge of this life threatening infection, so that their advice and
drug therapies are optimal and effective. Lastly the pharmaceutical companies that
manufacture these drugs might be persuaded to make their products more affordable for
those individuals who are most at risk. We need to utilize our limited options to the
fullest until such a time as the ultimate challenge is realised - an effective malaria
vaccine. === Andrew Chakane 2018
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