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K Mølbak

Publications and source records attributed to K Mølbak.

16 recordsLinked to original sources

[Parasitic diseases in patients with impaired immune response. Clinical picture and diagnosis].

Patients with impaired immune system are frequently infected with various parasitic diseases. The clinical picture is characterized by unusual manifestations and frequently severe recurrences of infections which are not normally serious. Some almost parasitic microorganisms produce symptoms exclusively in patients with impaired immune system. Parasitic infections have become increasingly common with the increasing number of patients who live for prolonged periods with impaired immune systems, often as a result of infection with HIV. Among the numerous parasitic infections which are observed in man, there are a few which occur particularly frequently in patients with impaired immune systems. This is a brief review of the clinical pictures and diagnostic options in parasitic disease in individuals with impaired immune system with particular emphasis on infections caused by: Pneumocystis carinii, Toxoplasma gondii, Cryptosporidium ssp., Microspora, Entamoeba histolytica, Leishmania ssp., and Strongyloides stercoralis. In patients with impaired immunity, parasitic infections frequently cause nonspecific symptoms and, on account of the impaired immunity, antibodies to the parasite are not always produced. The diagnosis of these infections is, therefore, based on morphological demonstration of the microorganism concerned, culture, specific antigen or DNA defections.

Acquired Immunodeficiency Syndrome

Lack of evidence of vertical transmission of human immunodeficiency virus type 2 in a sample of the general population in Bissau.

Twenty-nine human immunodeficiency virus type 2 (HIV-2) seropositive women identified in a cross-sectional study in Bissau in 1987 participated in a follow-up study in 1988, where each was matched for age and marital status with two HIV-2 seronegative women. Detailed information about all pregnancies was obtained. The HIV-2 seropositive women and their controls had similar mean numbers of pregnancies, live children, children who died, and abortions. The HIV-2 seropositive women did not have a greater risk of having had an abortion or a child who died than did the HIV-2 seronegative women. No difference in survival was seen between children born to HIV-2 seropositive and HIV-2 seronegative women. The H/S-ratios and CD4 numbers were lower in the seropositive group, but none had values lower than 0.4 and 0.4 x 10(9)/L, respectively. Seven prospectively observed children born to HIV-2 seropositive mothers showed no sign of infection. The lack of evidence of transmission of HIV-2 from mother to child is suggested to be due to the absence of marked immunodeficiency in this random sample of the general population.

Adult

Siblings of opposite sex as a risk factor for child mortality.

OBJECTIVE: To examine whether contracting an infection from a sibling of the opposite sex affects child mortality. DESIGN: Retrospective study of twins and case-control study of randomly selected children conducted within a prospective cohort study. SETTING: Urban and rural areas of Guinea-Bissau. SUBJECTS: 251 Pairs of twins (65 male pairs, 72 female pairs, and 114 mixed pairs), and 39 children who died and 78 controls identified in a cohort of 853 children aged less than 4, comprising 772 randomly selected children, all twins, and all children who had measles living in Bandim 2. MAIN OUTCOME MEASURES: Death of a child and sex of cotwin or older sibling nearest in age. RESULTS: The mortality among children from mixed pairs of twins was higher than that among pairs of the same sex (relative risk 1.47, 95% confidence interval 1.14 to 1.90). Boys had a slightly higher mortality especially in the older groups. In the case-control study the older sibling nearest in age was of the opposite sex for 29 (74%) of the children compared with 36 (46%) of the controls matched for age, sex, and area. Mortality was higher among both boys and girls with older siblings of the opposite sex than among those with siblings of the same sex (odds ratio 1.90, 0.78 to 4.61 v 7.5, 1.59 to 35.30), but the difference was more pronounced among girls. CONCLUSIONS: Children whose older sibling nearest in age is of the opposite sex or who have cotwins of the opposite sex have a higher mortality from infectious diseases. Further investigation is needed to determine the nature of this relation.

Adolescent

An epidemic outbreak of cryptosporidiosis: a prospective community study from Guinea Bissau.

In the first year of a prospective community study of childhood diarrhea conducted in a semiurban area in the capital of Guinea Bissau, Cryptosporidium sp. was found in 73 (6.0%) of 1216 episodes of diarrhea. The parasite was the second most prevalent intestinal parasite, and the only one significantly associated with diarrhea (OR = 2.79, P = 0.0006). The seasonal distribution was striking, with a peak prevalence in the beginning of the rainy season (May 17.6%) when an epidemic outbreak of diarrhea started. The prevalence was highest in children younger than 18 months, an age at which prevalences of other intestinal parasites were low. This reverse age pattern may possibly be explained by the small infective dose needed to create severe infections, by air-borne transmission and by the development of protective immunity.

Cryptosporidiosis

Immunodeficiency in HIV-2 infection: a community study from Guinea-Bissau.

In a community study in Guinea-Bissau, West Africa, 47 HIV-2-seropositive cases and 87 matched controls were evaluated immunologically using immuno-alkaline phosphatase linked to avidin-biotin complex for the assessment of CD4 and CD8 status. HIV-2-seropositive individuals had significantly lower total numbers of CD4 cells and CD4/CD8 ratios, 38% having a total number of CD4 cells less than or equal to 0.5 x 10(9)/l and 36% having a CD4/CD8 ratio less than or equal to 0.8. Total numbers of CD4 cells less than or equal to 0.5 x 10(9)/l or CD4/CD8 ratio less than or equal to 0.8 were found in 53% of the HIV-2 seropositives compared with 11% among controls [odds ratio (OR) = 7.3; 95% confidence interval (CI): 3.1-17.1]. Lymphadenopathy was significantly more frequent among HIV-2 seropositives than among controls (OR = 3.4; 95% Cl: 1.5-7.6). HIV-2 seropositives with lymphadenopathy had significantly fewer lymphocytes (P = 0.008) and lower total CD4 (P = 0.029) and total CD8 number (P = 0.011) than HIV-2 seropositives without lymphadenopathy. This study indicates that HIV-2 has a significant immunosuppressive effect.

Adult

Prevalence of and mortality from human immunodeficiency virus type 2 in Bissau, West Africa.

In a community based prevalence study of HIV infection in Bissau, West Africa, 1987, the population in 100 randomly selected "houses" was asked to participate. 89% (1329/1499) were examined and had a blood sample taken. None was HIV-1 seropositive but 4.7% were seropositive for HIV-2 (0.6% in children, 8.9% in those aged 15 years and over, and 20% in those aged 40 years and over). There was no significant difference in seroprevalence between areas or ethnic groups or between individuals of different civil status when age was taken into account. Sexual contact and blood transfusions were the dominant transmission routes, and no case of vertical transmission was identified. The HIV-2 seroprevalence in spouses of HIV-2 seropositive index persons was 40%. For a history of blood transfusion the relative risk of being HIV-2 seropositive was 103.6 in children and 2.4 for adults. After exclusion of spouses, no clustering of HIV-2 seropositivity was seen. At follow-up, after a mean observation time of 325 days, there was an excess mortality for HIV-2 seropositives. The relative risk of dying for HIV-2 seropositive children was 60.8 and for adults 5.0.

Adolescent

Bacterial contamination of stored water and stored food: a potential source of diarrhoeal disease in West Africa.

The food and water hygiene in two Liberian communities was studied in a house-to-house diarrhoea survey. The level of contamination with enterobacteria of drinking water stored in the households was significantly higher than at the water sources. Food hygiene standards were low, particularly in the urban slum where storage of cooked food for long periods led to bacterial multiplication at high levels. Infant foods were particularly heavily contaminated. It is concluded that when water supply programmes are planned, the presence of other risk factors for water-related diseases should be investigated. To ensure maximum health benefits, water projects should as a rule be accompanied by other interventions.

Child, Preschool

High prevalence of campylobacter excretors among Liberian children related to environmental conditions.

Campylobacter was the bacterial pathogen most prevalent in 859 children, aged 6-59 months, examined in a house-to-house diarrhoea survey in two Liberian communities. 44.9% of the children from an urban slum and 28.4% from a rural area were excretors. Since the prevalence of diarrhoea was very high and consequently many convalescent carriers were found, it was not possible to evaluate the pathogenic role of campylobacter. The excretor rate increased with age and was significantly correlated to the use of supplementary feeding, inversely correlated to the quality of the water supply, and also associated with helminthic infestation. Results from re-examination of 172 children suggested a high intensity of transmission. The findings all indicate the existence of a heavy environmental contamination with campylobacter, probably of both human and animal faecal origin.

Breast Feeding

Soluble Plasmodium falciparum antigens contain carbohydrate moieties important for immune reactivity.

The importance of carbohydrate moieties for the antigenicity of purified soluble Plasmodium falciparum antigens from the asexual blood stage was tested. Digestion of the soluble antigens with alpha-D-galactosidase clearly affected the ability of the antigen to react with malaria-immune sera from different geographical origins in crossed immunoelectrophoresis and immunoblotting. Antigens of 220, 180, 80, and 74 kilodaltons were affected by the enzyme treatment. Furthermore, the enzyme digestion reduced the ability of the purified soluble antigen to stimulate lymphocytes from malaria-immune donors. The results might have important implications for the strategy of developing a malaria vaccine.

Animals

Cryptosporidium spp., a frequent cause of diarrhea in Liberian children.

This report presents results from a sample survey designed to investigate the possible role of Cryptosporidium spp. in childhood diarrhea in a developing country, Liberia, West Africa. During the four months of January to April 1983, a house-to-house study was carried out in two geographically and socially different communities--an urban slum and three rural villages. Stool samples from 374 children, aged 6 to 59 months, were tested for Cryptosporidium spp. Among the children with diarrhea 8.4% were Cryptosporidium spp. positive compared with a prevalence rate of 5.9% in asymptomatic children. Of the children living in a household with a Cryptosporidium spp.-positive index child, 8.6% had a positive stool sample. Of all children attending a clinic because of diarrhea, 14.6% were Cryptosporidium spp. positive. Cryptosporidiosis was more frequent in younger children; 24 of the total of 29 positive cases (83%) were below 2.5 years old. Actual or previous bottle feeding (formula) was a risk factor, particularly in children below 18 months old. Of the bottle-fed children, 28% were Cryptosporidium spp. positive versus 9.1% of children never bottle fed. Crowding is another possible risk factor. The prevalence of cryptosporidiosis was 13.5% in big urban households with more than 10 children, whereas the prevalence in the small urban households was 6.1%. Ethnic and religious differences were particularly evident in the rural area. No Muslim households had cryptosporidiosis, whereas the prevalence in non-Muslim tribes was 9%. The general belief that cryptosporidiosis is primarily a zoonosis is questioned in this study, partly because many carriers and asymptomatic household contacts were found.

Age Factors

Persistent and acute diarrhoea as the leading causes of child mortality in urban Guinea Bissau.

An investigation of child mortality in a semi-urban community, Bandim II, in the capital of Guinea Bissau was carried out from April 1987 to March 1990. 153 deaths were recorded among 1426 live-born children who were followed for 2753 child-years. The under-five mortality risk was 215 per 1000 children (95% confidence interval [CI] 176-264), infant mortality 94 per 1000 (95% CI 73-115), and perinatal mortality 52 per 1000 (95% CI 41-63). By prospective registration of morbidity, post-mortem interviews, and examination of available hospital records, a presumptive cause of death was established in 86% of the deaths. Persistent and acute diarrhoea were the most frequent causes of death, accounting for 43 and 31 deaths per 1000 children, respectively. Fever deaths (possibly malaria), neonatal deaths, acute respiratory infections, and measles were other frequent causes. The access to health services was relatively easy: 75% of the children who died had attended for treatment at a hospital or a health centre. It is important to find ways of preventing and managing persistent diarrhoea, the major cause of death, and to improve the control of acute diarrhoea by a targeted approach.

Acute Disease