Use of phenolic glycolipid 1 for serodiagnosis of leprosy in a high prevalence village in Papua New Guinea.

This study reports on the usefulness of an IgM phenolic glycolipid 1 (PGL-1) ELISA for serodiagnosis of leprosy in the first year of a prospective longitudinal community survey in a high (8.8%) prevalence village in Papua New Guinea. The IgM PGL-1 ELISA had limited value as a screening method for detection of new cases. Many normal persons, particularly children, had elevated IgM anti-PGL-1 antibodies, presumably a consequence of early subclinical infection.

Intestinal parasites in Zambian patients with AIDS.

Previous studies have found a high prevalence of Isospora belli and Cryptosporidium parvum infections in African acquired immune deficiency syndrome (AIDS) patients with chronic diarrhoea. We aimed to determine the prevalence of gastrointestinal parasite in AIDS patients in hospital, not only those with diarrhoea, and to compare them with the general community. Clinically diagnosed AIDS patients in a Zambian teaching hospital were interviewed and examined, and stool specimens were studied for parasite infection. A control group was recruited from adults in a township near Lusaka. Of 90 AIDS patients (58% male), 50 (56%) had chronic diarrhoea and 9 (10%) had diarrhoea of shorter duration. In the control group (105 adults; 85% female), only one complained of diarrhoea. A variety of intestinal protozoa and helminths was found in 57% of AIDS patients and 88% of the community members. Isosporiasis was detected in 7, and cryptosporidiosis in 2, AIDS patients, all with diarrhoea, but not in any control. Strongyloides was found in 2 AIDS patients with diarrhoea and one community resident. Hospital patients with AIDS had fewer Entamoeba coli and E. histolytica infections, probably because of previous chemotherapy. We conclude that AIDS predisposes to isosporiasis and cryptosporidiosis, but not to infection with extracellular intestinal parasites, such as Entamoeba species, Blastocystis, Chilomastix, Endolimax, Ascaris and Necator.

The epidemiology of leprosy in a high prevalence village in Papua New Guinea.

In a village of about 1000 people in Papua New Guinea the prevalence of clinical leprosy was 8.6% compared to about 3% in surrounding villages. This exceptionally high prevalence could not be explained by recent introduction of the disease or by social factors. Dapsone-resistant disease and faulty compliance with treatment are considered to be contributory to persistent infectivity of old cases which, together with the presence of 20 previously undiagnosed cases, comprised a large infective source. Social ostracism of cases was not observed and the extensive social mixing of all ages would facilitate widespread dissemination of infection. A high prevalence, particularly in children, of elevated levels of IgM antibody to phenolic glycolipid-1 Mycobacterium leprae specific antigen suggests frequent subclinical infection. The greater prevalence of clinical leprosy following childhood in the village favours altered susceptibility following exposure in childhood. There was a higher prevalence of leprosy in close relatives of cases when compared with the same relatives of age and sex matched leprosy-free controls. The occurrence of familial clustering of leprosy in a hyperendemic area with intense transmission suggests that unidentified inherited factors influence susceptibility to clinical leprosy. It is suggested that the clustering of adverse inherited traits through intermarriage may explain this hyperendemic focus on leprosy.

Hepatitis B surface antigenaemia in Kenyans with chronic liver disease.

Fifty Kenyan patients with chronic liver disease or hepatocellular carcinoma were tested for hepatitis B surface antigenaemia by radioimmunoassay. The hepatitis B surface antigen was detected in 77% of the patients with chronic persistent or chronic aggressive hepatitis, or cirrhosis confirmed by liver biopsy, compared with 15% in a control group. All six patients with hepatocellular carcinoma had detectable hepatitis B surface antigen or antibody. 50% of the controls had hepatitis B surface antibody in their plasma detectable by haemagglutination. Auto-immune associated liver disease appeared infrequent. The possibility that the hepatitis B virus is an important cause of cirrhosis in Kenya is discussed.

The significance of hepatitis B antigenaemia in symptom-free blood donors in Kenya.

One-hundred and eight blood donors found to have hepatitis B antigenaemia have been examined for evidence of liver disease. In five the liver was enlarged, and in six apparently normal donors there was histological evidence of disease. One or more tests of liver function were abnormal in an additional fifty-three donors without definite evidence of disease. Estimation of serum transaminases was the most reliable test and we recommmend that these be measured in all antigen-positive donors.

Portal vein thrombosis in adults.

Idiopathic thrombotic occlusion of the extrahepatic portal vein is one of the commonest causes of portal hypertension in adult Blacks. The condition occurs more frequently in men and may be accompanied by evidence of minor functional impairment of the liver. Associated pancytopenia is quantitatively related to the degree of splenomegaly. Assessment of a spectrum of variables of blood coagulation and fibrinolysis, while failing to shed light on the possible pathogenesis, does suggest a rational basis for thrombolytic therapy.

Dysfibrinogenaemia and primary hepato-cellular carcinoma.

The mechanisms of blood coagulation and fibrinolysis have been evaluated in 28 black adult Africans with primary hepato-cellular carcinoma (HCC). A characteristic pattern of abnormalities has been defined. Dysfibrinogenaemia appears to be a useful biological marker for the disease. The reptilase test (RT) is a simple, reliable and sensitive means of detection of this metabolic abnormality. It is suggested that the RT should be used to screen populations at high risk of developing HCC, such as cirrhotics, in conjunction with alpha fetoprotein determinations, which, alone, are inadequate for the purpose. The haemostatic defect may have relevance to the pathogenesis of HCC, and further suggests a potentially useful, additional, therapeutic modality.

Hepatitis Bs antigen and liver cancer: A population based study in Kenya.

Peers and Linsell (1973) demonstrated a significant association between the incidence of primary liver cancer and ingested aflatoxin in a study in the Muranga district of Kenya. A study of hepatitis B antigen in the same district showed no significant differences between the low altitude area, with a relatively high incidence of primary liver cancer, and the high altitude area with a lower incidence of the tumour. Current evidence is more in favour of aflatoxin playing an important role in the aetiology of primary liver cancer but hepatitis B antigen may play an ancillary role.

IgM serum antibodies to phenolic glycolipid-I and clinical leprosy: two years' observation in a community with hyperendemic leprosy.

A village population with hyperendemic leprosy in Papua New Guinea was repeatedly examined for clinical leprosy and for serum IgM antibodies to phenolic glycolipid-I (APGL-I) over 2 years between 1984 and 1986. In 1984, serum APGL-I was elevated in 15% of the subjects without clinical leprosy, and the prevalence of seropositivity was not significantly different in subjects from households with or without leprosy. In 1986, the prevalence of elevated serum APGL-I in leprosy-free subjects had risen to 23%. The incidence of seroconversion from APGL-I negative to APGL-I positive was 9.5% per year (95/1000 person years) in 253 subjects tested in 1984 and 1986. During the same period, 27 of 40 (67%) leprosy-free subjects reverted from positive to negative. The positive seroconversion rate in the community was higher than the incidence of clinical leprosy (11.2/1000 person years) over the same period. However, elevated serum APGL-I was not associated with clinical disease and failed to predict the development of disease over 2 years. The significance of persistent seropositivity found in 14 (5%) leprosy-free subjects is uncertain.

Use of prednisolone in the treatment of HIV-positive tuberculosis patients.

Corticosteroids are beneficial in the treatment of some forms of tuberculosis, but their role in TB affecting HIV-positive patients is not clear. During a cohort study of tuberculosis patients in Lusaka, Zambia, prednisolone was prescribed for specific indications. Six of 47 (13 per cent) of patients who received prednisolone early in treatment developed herpes zoster, compared with 2 of 118 (2 per cent) of those who did not. Three patients who received prednisolone developed Kaposi's sarcoma, compared with none who did not. At 2 months patients who had received prednisolone showed a greater improvement in generalized lymphadenopathy and cough. Controlled studies of the risks and benefits of administration of corticosteroids to HIV-positive TB patients are urgently needed.

BCG vaccination in leprosy: final results of the trial in Karimui, Papua New Guinea, 1963-79.

The efficacy of BCG vaccine in preventing the clinical manifestations of leprosy in a tuberculosis-free area of Papua New Guinea is reported. Between 1963 and 1966 a total of 5356 subjects, randomized to receive BCG or saline inoculations, were examined for leprosy before the vaccination and surveillance was continued until 1979. BCG afforded 48% protection against clinical leprosy, being most effective against borderline tuberculoid leprosy and in children vaccinated when under 15 years old. Protection was evident within 12 months in those vaccinated between the ages of 10 and 15 years but was delayed in other age groups. There was evidence for accelerated manifestations of tuberculoid leprosy in children vaccinated when under 5 years of age. Tuberculin sensitivity was more likely to be sustained following multiple BCG inoculations; vaccinees with sustained tuberculin sensitivity had the lowest incidence of leprosy, but protection was also evident in tuberculin-negative vaccinees. These results may have implications for ongoing trials of leprosy vaccine incorporating BCG.