The chemotherapy of onchocerciasis X. An assessment of four single dose treatment regimes of MK-933 (ivermectin) in human onchocerciasis.

Nineteen patients from an area of vector control in the savanna region of Northern Ghana, all with moderate to heavy infections with Onchocerca volvulus and some with ocular involvement, were treated with 50, 100, 150 or 200 micrograms kg-1 of ivermectin. Detailed monitoring of clinical and ocular reactions and of alterations in skin microfilarial counts and laboratory indices were carried out during the first 28 days. Microfilarial counts in skin snips and detailed ocular examinations were then repeated at intervals over a period of nine months. Ivermectin slowly eliminated microfilariae from the skin and eye without serious adverse clinical or ocular reactions in all treated groups. There was little difference in efficacy between doses of 100, 150 and 200 micrograms kg-1, and these were more effective than the 50 micrograms kg-1 dose. Very low levels of skin microfilariae were maintained for nine months. Microfilariae were not eliminated from the eye for at least three months. The drug was neither macrofilaricidal nor embryotoxic. However, it produced a dose-dependent stimulation of embryogenesis manifest at one month and succeeded by a suppression of embryogenesis at three months after therapy. In areas where transmission of onchocerciasis has been interrupted, ivermectin may need not be given more often than once a year. The efficacy of the drug on single dosage and the mild adverse reactions produced, if confirmed in subsequent controlled studies, would greatly simplify the treatment of onchocerciasis and would reintroduce new concepts of the role of chemotherapy in the control of onchocerciasis.

Cardiac response of Nigerian hypertensives to anaesthesia and surgery.

This study was undertaken to determine the cardiac response of Nigerian hypertensives to anaesthesia and surgery, using systolic time intervals as an indication of ventricular function. Nine hypertensive and eight normotensive patients who were admitted for various operations had carotidogram, phonocardiogram and electrocardiogram recorded simultaneously before induction of anaesthesia, after induction and during operation. The pre-ejection phase, (PEP) and the left ventricular ejection time (LVET) were measured from the tracings and the ratio PEP/LVET was calculated. The results showed that for both normotensive patients and hypertensive patients there was a mean increase of the PEP/LVET ratio under anaesthesia and surgery, indicating deterioration of ventricular function. Hypertensive patients showed a much greater deviation from normal, approaching heart failure values. It is concluded that hypertensive patients seemed to be at greater risk during anaesthesia and surgery. The implication is that hypertensive patients should be adequately treated before operation.

Skin tests in Nigerian asthmatics from the equatorial forest zone in Benin, Nigeria.

Forty-two patients with bronchial asthma from the Benin area and 32 control subjects were subjected to skin prick tests for groups of allergens. There was a significant excess of reactions of 5 mm or over to Dermatophagoides farinae amongst the asthmatics. This was the most commonly detected allergen. There was an overall excess in asthmatics of positive reactions of over 5 mm in the other groups although there was no significant excess in any single group. There was no significant difference in the weaker skin reactions (less than 5 mm between) asthmatics and controls. From clinical histories most precipitating factors known to patients were probably non-allergic in origin, exercise, irritant odours, dust and climatic changes being the commonest. Sets of allergens specially prepared for West Africa would be valuable for skin testing asthmatics in this environment.

Forty-seven cases of pyogenic meningitis in adults in Korle Bu Hospital, Accra.

Forty-seven cases of pyogenic meningitis treated at Korle Bu Hospital are described. Twenty-two were pneumococcal and in the other 25 no organisms were isolated from the C.S.F. The mortality rate was high (62%). Late presentation, extracerebral sepsis and fulminant infection were common. Clinical features, reasons for the high mortality rate, treatment and possible measures to improve the situation are discussed.