UNCOMPLICATED MALARIA IN NON-IMMUNES Presentation of uncomplicated P. falciparum
malaria is very variable and may mimic that of many other diseases. Non-immune patients with uncomplicated malaria are prone to the development of severe P. falciparum
malaria. Life threatening complications can develop rapidly in these patients. SYMPTOMS
Although fever is very common, it is absent in some cases. The fever is initially persistent rather than
tertian. In addition some of the following symptoms may arise:
TREATMENT It is
recommended that these patients receive the most effective treatment regimen available. Ideally, treatment should be initiated in hospital.
The regimens for the treatment of uncomplicated malaria are given in Table 1.
Sulfadoxine-Pyrimethamine The combination of sulfadoxine and pyrimethamine has been a successful
operational drug in areas of chloroquine resistance. The use of this combination is, however, becoming limited due to the presence of sulfadoxine-pyrimethamine-resistant parasites
1,2,10 and the risk of severe cutaneous adverse effects.11
It is recommended for the treatment of mild malaria infections acquired in South Africa. Since sulfadoxine is a sulphonamide, it is contra-indicated in patients exhibiting sulphonamide hypersensitivity. Sulfadoxine-pyrimethamine is a slow acting schizonticide and should not be used alone when there is a high risk of severe or complicated malaria.
Quinine
Quinine as a single agent should be sufficient to treat most cases of uncomplicated malaria, as quinine resistance has infrequently been reported in South Africa. Oral quinine therapy
is recommended, but the initial doses of quinine may be administered intravenously if the patient is vomiting. Quinine therapy should be continued for at least 7 days or until the
blood smear is negative.The addition of a second antimalarial is only indicated if the patient contracted the infection in a country with suspected quinine resistance (e.g.
South America and Asia). Either doxycycline or sulfadoxine- pyrimethamine can be added. One of these should be added 2-3 days after commencement of the quinine to ensure that
possible adverse effects from the quinine are not confused with those of the second agent. Doxycycline or other tetracyclines should not be used in patients less than 8 years of
age or during pregnancy. Minor adverse effects, forming a syndrome known as cinchonism, are almost the rule during the treatment of malaria with quinine. Mild hearing
impairment (notably high tone deafness), tinnitus, headache, nausea and slight visual disturbances are common, occurring in up to 70% of patients during quinine therapy. Hypoglycaemia
is the most serious frequent adverse side-effect. Major side effects include arrhythmias, hypersensitivity and hypoglycaemia. Quinine toxicity presents with CNS
disturbances (visual and auditory most common manifestations) and cardiovascular abnormalities (hypotension, heart block, ventricular arrhythmias), which can be confused with severe
(complicated) malaria. Quinine levels can be used to differentiate these syndromes.11 Chloroquine Chloroquine has been the favoured treatment for
susceptible (chloroquine-sensitive) malaria as it is effective, well-tolerated and cheap. The use of chloroquine alone is now limited because of wide-spread resistance1,2,10
but remains effective against malaria acquired in Central America, the Caribbean and some countries in the Middle East.13
The degree and extent of chloroquine resistance in South Africa has not been adequately documented. However, it is presumed, and generally accepted, that resistance to chloroquine is too high to recommend its use as treatment unless monitoring of treatment response shows that it remains effective.
The guidelines are endorsed
by the Medical Association of South Africa. |
