Magnetic resonance imaging T1 indices of the brain as biomarkers of inhaled manganese exposure.

Excessive exposure to manganese (Mn) is linked to its accumulation in the brain and adverse neurological effects. Paramagnetic properties of Mn allow the use of magnetic resonance imaging (MRI) techniques to identify it in biological tissues. A critical review was conducted to evaluate whether MRI techniques could be used as a diagnostic tool to detect brain Mn accumulation as a quantitative biomarker of inhaled exposure. A comprehensive search was conducted in MEDLINE, EMBASE, and PubMed to identify potentially relevant studies published prior to 9 May 2022. Two reviewers independently screened identified references using a two-stage process. Of the 6452 unique references identified, 36 articles were retained for data abstraction. Eligible studies used T1-weighted MRI techniques and reported direct or indirect T1 measures to characterize Mn accumulation in the brain. Findings demonstrate that, in subjects exposed to high levels of Mn, deposition in the brain is widespread, accumulating both within and outside the basal ganglia. Available evidence indicates that T1 MRI techniques can be used to distinguish Mn-exposed individuals from unexposed. Additionally, T1 MRI may be useful for semi-quantitative evaluation of inhaled Mn exposure, particularly when interpreted along with other exposure indices. T1 MRI measures appear to have a nonlinear relationship to Mn exposure duration, with R1 signal only increasing after critical thresholds. The strength of the association varied depending on the regions of interest imaged and the method of exposure measurement. Overall, available evidence suggests potential for future clinical and risk assessment applications of MRI as a diagnostic tool.

Quality control for parasitologic data.

Accuracy of data is of paramount concern for all research. The task of providing objective assurances of accuracy of parasitologic data for a large, multi-center epidemiologic research project in Egypt (Epidemiology 1, 2, 3 [EPI 1, 2, 3]) presented a unique set of challenges undertaken jointly by the Ministry of Health's Qalyub Center for Field and Applied Research with technical assistance from Tulane University (New Orleans, LA). The EPI 1, 2, 3 project was part of large bilateral research program, the Schistosomiasis Research Project, undertaken jointly by the governments of Egypt and the United States. This paper describes the nature of the quality control system developed to accomplish this task, presents results and discusses the findings.

The epidemiology of schistosomiasis in Egypt: Qalyubia Governorate.

The primary objectives of this study, carried out in Qalyubia Governorate in Egypt (south-central Nile Delta), were to continue tracking historical trends of infection prevalence of Schistosoma mansoni and S. haematobium, determine whether satellites (ezbas) of mother villages differed significantly with respect to schistosomiasis transmission, and to asses schistosomiasis-induced morbidity on a population basis using ultrasonography. Our study revealed that S. haematobium has virtually disappeared from Qalyubia governorate, and that S. mansoni prevalence continues to decline slowly (17% in 1991 compared with 19% in 1990). The prevalence of intestinal schistosomiasis was actually higher in the mother villages than in the ezbas of the same villages, indicating that prevalence based on surveys of villages alone did not (at least for Qalyubia) cause underestimates of true prevalence. (A mother village is the large village in an area that includes hamlets or ezbas. In many areas, the infection rate in ezbas is significantly higher than in the larger central village.) Ultrasonographic studies revealed that less than 3% of the population had stage 2 or stage 3 periportal fibrosis, commonly associated with chronic schistosomiasis mansoni. This low level of morbidity was consistent with earlier data from Qalyubia, which also showed a low level of S. mansoni-induced morbidity in this governorate.

The epidemiology of schistosomiasis in Egypt: summary findings in nine governorates.

Health questionnaires and parasitologic examinations of urine and stool were evaluated from a stratified random sample of 89,180 individuals from 17,172 households in 251 rural communities in 9 governorates of Egypt to investigate the prevalence of, risk factors for, and changing pattern of infection with Schistosoma sp. in Egypt. A subset, every fifth household, or 18,600 subjects, had physical and ultrasound examinations to investigate the prevalence of and risk factors for morbidity. Prevalence of S. haematobium in 4 governorates in Upper Egypt in which it is endemic ranged from 4.8% to 13.7% and averaged 7.8%. The geometric mean egg count (GMEC) ranged from 7.0 to 10.0 ova/10 ml of urine and averaged 8.1. Age stratified prevalence of infection peaked at 15.7% in the 10-14-year-old age group and decreased to 3.5-5.5% in all groups more than 25 years of age. Age-stratified intensity of infection peaked at approximately 10.0 ova/10 ml of urine in the 5-14-year-old age groups and was about half that in all groups more than 25 years of age. Males had higher infection rates and ova counts than females in all age groups. Schistosoma mansoni was rare in Upper Egypt, being consequential in only Fayoum, which had a prevalence of 4.3% and an average intensity of infection of 44.0 ova/g of stool. Risk factors for S. haematobium infection were male gender, an age <21 years old, living in smaller communities, exposures to canal water; a history of, or treatment for, schistosomiasis, a history of burning micturition or blood in the urine, and reagent strip-detected hematuria or proteinuria. The more severe grades (II and III) of ultrasonography-detected periportal fibrosis (PPF) were rare (15 of 906) in these schistosomiasis haematobia-endemic governorates. Risk factors for morbidity (ultrasonography-detected urinary bladder wall lesions and/or obstructive uropathy) were similar to those for infection, with the exception that risk progressively increased with age. Subjects with active S. haematobium infections were 3 times as likely as those without active S. haematobium infections to have urinary tract morbidity. The prevalence of S. mansoni in 5 governorates in Lower Egypt, where it is endemic, ranged from 17.5% to 42.9% and averaged 36.4%. The GMEC ranged from 62.6 to 93.3 eggs/g of stool and averaged 81.3. Age-stratified prevalence of infection peaked at 48.3% in the 15-19-year-old age group, but averaged 35-45% in all groups more than 10 years of age. The intensity of infection was highest in the 10-14-year-old age group, and showed a range of 70-85 eggs/g of stool in those > or =5 years of age. Males had higher infection rates and ova counts than females in all age groups. Schistosoma haematobium was rare in these governorates; Ismailia (1.8%) had the highest infection rate. Risk factors for S. mansoni were male gender, an age >10 years old, living in smaller communities, exposures to canal water, a history of, or treatment for, schistosomiasis or blood in the stool, detection of splenomegaly by either physical examination or ultrasonography, and ultrasonography-detected PPF. The more severe grades (II and III) accounted for 463 (13.3%) of the 3,494 having ultrasonography-detected PPF. Risk factors for morbidity (ultrasonography-detected PPF) were similar to those for infection except that inhabitants of smaller communities were not at increased risk. Active S. mansoni infection increased the odds ratio (OR) of having PPF by 1.37. In comparison with others with normal-size livers, subjects having hepatic enlargement in either the midclavicular line or the midsternal line detected by physical examination or ultrasonography had a reduced risk (ORs = 0.64-0.72) of PPF. The prevalences of lesions detected by ultrasonography were 23.7% for enlargement of right lobe of the liver, 11.3% for enlargement of left hepatic lobe, 20.6% for splenomegaly, and 50.3% for PPF. Schistosoma mansoni has almost totally replaced S. haematobium in Lower E

Anthropological contributions to a community-based schistosomiasis control project in northern Cameroun.

This paper describes how anthropological contributions and extensive cooperation between tropical medicine and medical anthropology researchers contributed to a successful community-based cost recovery schistosomiasis control project in northern Cameroun. The project led to increased knowledge about urinary schistosomiasis by local people, significant decreases in prevalence and intensity of the disease, and increased utilization of primary health care centers.

Ivermectin distribution and the cultural context of forest onchocerciasis in South Province, Cameroon.

This investigation examined the cultural context of forest onchocerciasis in several communities in the Dja-Lobo Division of southern Cameroon. The study sought to elucidate behaviors that would enhance or diminish health status relative to forest onchocerciasis and other filarial infections, and to make culturally sensitive and appropriate recommendations regarding the development of health education materials and the long-term sustainability of the ivermectin distribution program in Dja-Lobo. The study consisted of two sequential components; the first was a qualitative study of a few severely affected villages and the second was a quantitative study of 212 randomly selected heads of households from eight villages. The Boulou and Baka peoples in these communities defined general filariasis (minak) as small worms under the skin, identified flies as important transmitters of the illness, and indicated that blindness and other skin and ocular problems were a consequence of the illness. Illness of the Dja (referring to an illness found near the Dja River) was another illness that was closely linked to onchocerciasis; local people indicated it was transmitted by the black flies found near the Dja River, resulting in severe itching and leopard skin. These and other cultural-behavioral data on filariasis were used to implement a health education and distribution program.

PIP: The cultural context of forest onchocerciasis was studied in the Boulou and Baka ethnic communities in the Dja-Lobo Division of southern Cameroon. A 2-day survey used focus group interviews followed by a questionnaire administered to 212 randomly selected individuals in 8 communities (88 male and 124 females heads of household) to assess their knowledge about onchocerciasis. Most people (98%) had some knowledge about the disease. Minak was the term used for filariasis by most people (97%) and people knew (90%) that black fly (nyamendimi) was responsible for its transmission. Other vectors of the illness identified were mosquitoes, dirty water, sorcery, and taboo foods. 81% thought that maternal transmission was possible and 66% indicated that filariasis could be transmitted sexually. Virtually all respondents associated itching and rash with minak (filariasis) and more than 60% also recognized the swelling of the skin and leopard skin as manifestations of filariasis. Filariasis, malaria, worms, and blindness were placed in the middle category when the severity of various diseases was ranked by 20 Boulou adults. In contrast, the Baka did not think that filariasis caused blindness, nor that it is linked to eye-worms. However, the 212 individuals ranked blindness as the most severe among other diseases (filaria, malaria, diarrhea, and intestinal worms). 80% of the Boulou and Baka adults had had filariasis in the previous year, but only 5% of the Boulou children and none of the Baka children had had filariasis during that time period. With respect to intestinal worms, 71% of the Boulou adults and 60% of the Baka adults had had intestinal worms in the previous year, while more than 90% of the Boulou children and all of the Baka children had had intestinal worms. Of the 90% who revealed that they had had filariasis at least once before, 69% sought treatment. 54% had tried traditional treatment, while 50% had tried Notezine, 49% had tried Phenergan, and 38% had tried M.G. Lumiere.

Disease evaluated on return-to-work examinations: aviation ground personnel compared to other workers.

Aviation ground personnel are subjected to a wide range of chemical and physical exposures that may lead the occupational physician to see a different spectrum of morbidity in the airport compared to other settings. It is essential to determine the most common medical problems in airport ground personnel in order to identify possible work-related conditions and in order to set the priorities for establishing health promotion programs and training occupational physicians. We compiled the diagnoses in 1000 consecutive visits of ground workers to the airport clinic for return-to-work examinations, and compared them to 7000 workers seen in general occupational clinics. The frequencies of the various categories of disease were similar in both type of clinics, except that low back pain was significantly more common in the ground personnel [251 (20.6%) vs. 1176 (15.2%), p < 0.003]. Over 80% of the diseases occurred in 10 diagnostic categories: cancer, fractures, hypertension, ischemic heart disease, knee pain, low back pain, neck pain, operations for various medical conditions, phonal trauma, and pregnancy. We conclude that, except for low back pain, the spectrum of disease seen in the airport clinic is not significantly different from that seen in general occupational medicine clinics. Focusing on the interaction of a limited number of diseases with the work environment will provide the occupational physician with a comprehensive training program, and the emphasis needed for establishing health promotion programs.

Community-based approach to schistosomiasis control.

With few exceptions, efforts to control schistosomiasis have relied upon ongoing community cooperation with "outsiders' rather than creating within the community the capacity and means for carrying out ongoing disease control measures with minimal external support. Offered as a useful model is a program in Kaele subdivision, Extreme North Province, Cameroon designed to establish and integrate within the primary health care (PHC) system the control of urinary schistosomiasis, hyperendemic in the region. At the community level, and with minimal dependence upon external resources, culturally appropriate and effective health education was instituted, the capacity to diagnose and treat schistosomiasis was created, diagnosis and drug therapy (praziquantel) was made available conveniently and at low cost, and, on a very limited basis, snails were controlled. Efforts were made to build upon and strengthen existing community structures and institutions rather than create new ones. The impact of the interventions was measured in terms of changes in knowledge and behavior, prevalence and intensity of infection, utilization of health services, and the ability to finance the control activities within the context of a generalized cost recovery system. Program successes and failures are discussed, as well as lessons learned and their implications.

The impact of control measures on urinary schistosomiasis in primary school children in northern Cameroon: a unique opportunity for controlled observations.

As part of a program to integrate schistosomiasis control into the primary health care system in northern Cameroon, an unexpected opportunity to undertake a controlled evaluation of the impact of interventions was recognized. Inadvertently, a large part of Mindjil, one of four assessment villages, had been essentially excluded from the program, creating a unique natural control. The prevalence of infection with Schistosoma hematobium in school-aged children was 7% in the areas where the control program was implemented, and 71% in the excluded areas (P < 0.0002). High intensity infection was 1% and 26% in the two areas, respectively (P < 0.0002). Children in the school where the control interventions were implemented had a significantly lower prevalence of infection with Schistosoma hematobium (P < 0.005). Subjects in intervention areas demonstrated greater knowledge about the transmission of schistosomiasis than those in the control area. This study documented and quantified program impact in a controlled manner not usually possible in field studies and also illustrated how unrecognized intracultural diversity (within culture differences) in target populations may effect disease control programs in communities.

Common accidents among airport ground personnel.

Work-related accidents at the airport are common, but the incidence and type of such events occurring in aviation ground personnel have not been reported previously. Information regarding the most common ground accidents at the airport is essential in order to implement prevention programs. The purpose of this study was to examine the descriptive epidemiology of injury-producing accidents among ground personnel at a modern airline. In this study we recorded all reported accidents occurring over a 5-year period (1988-92) to workers of a major airline in Israel that resulted in 3 d or more of absence from work. During the study period 523 work-related accidents occurred in 2000 ground workers. The most common accidents were due to slips, trips and falls (n = 211, 40.3%), lifting and carrying accidents (n = 107, 20.4%), and machinery accidents (n = 98, 18.7%). Work transport accidents and accidents from physical and chemical exposures were less common (n = 67, 12.8%, and n = 40, 7.5%, respectively). The accident rate decreased from 71 accidents/1,000 worker-years in 1988 to between 40-56 accidents/1,000 worker-years in the subsequent 4-year period (p = 0.0002). We conclude that slips, trips and falls are the most common cause of accidents in airport ground personnel. Further studies in other airports are warranted to confirm our findings.

Evaluation of alternate methods of rapid assessment of endemicity of Onchocerca volvulus in communities in southern Cameroon.

Potential diagnostic indicators of onchocerciasis (subcutaneous nodules, depigmentation or leopard skin, microfilaruria, diethylcarbamazine patch test positivity, excoriations, and pruritus) were evaluated in a rain forest region of southern Cameroon for usefulness in rapid assessment of onchocerciasis endemicity in communities. Thirty-two study villages were selected, representing high, intermediate, and low prevalence levels, and 846 adult male residents of these communities 20 or more years of age were examined according to a defined protocol. Skin snips (from each iliac crest) served as the reference standard. Skin snip positivity was 75.5%; the effect of age was minimal. Leopard skin and nodules showed the strongest correlation with both the skin snip prevalence and community microfilarial load, as reflected by the adult male study population. We selected > or = 20% nodules or > or = 20% leopard skin as the most appropriate local criteria for assigning a community to high priority for control, which corresponds to a > or = 90% skin snip prevalence in adult males. While this criteria should not be applied to regions with savannah onchocerciasis, we believe the methodology can and should be used to determine appropriate diagnostic indicators for rapid assessment of Onchocerca volvulus endemicity in regions with different dynamics of transmission and clinical expression of disease.

Impact of Schistosoma haematobium infection and of praziquantel treatment on anaemia of primary school children in Bertoua, Cameroon.

There is some debate as to the extent to which Schistosoma haematobium haematuria may be the cause of anaemia. Our goal was to evaluate the impact of a single 40 mg kg-1 dose of praziquantel on anaemia. Since praziquantel does not reduce the hookworm intensity of infection (a major cause of anaemia in children in the area) changes in the prevalence of anaemia in the study population should be due only to the elimination of S. haematobium. Seven hundred and seventy-one primary schoolboys from Bertoua (East Cameroon) were divided into four groups: high infection, moderate infection treated with praziquantel or placebo, and non-infected. Haemoglobin concentrations of the children were determined at the onset of the study and 6 months after the praziquantel intervention. Mean haemoglobin concentrations were not significantly different for no infection or for mild or heavy infection by S. haematobium. A factorial analysis of variance using S. haematobium intensity of infection, malaria and intestinal parasite infections and age as independent variables and haemoglobin concentration as the dependent variable show that only age and malaria infection show a significant relationship with haemoglobin concentration. Despite treatment with praziquantel, all the children in the treatment groups had lower mean haemoglobins 6 months after intervention. A factorial analysis of variance using age, malaria infection and the treatment category as independent variables and the difference in haemoglobin concentration as the dependent variable shows that only malaria infection showed a significant relationship with haemoglobin concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Infective endocarditis: a challenging diagnosis.

The critical care nurse plays a key role in the management and care of the patient with Infective Endocarditis. The nurse's sensitive assessment of post-operative cardiac surgery patients helps to identify this complication in the early stages so that early antibiotic therapy can improve outcomes for patients with this complication. Likewise, the nurse's assessment which uncovers a history of recent dental techniques or drug abuse helps identify this complication in newly-admitted patients. By administering and evaluating the success of antibiotic therapy the nurse helps the patient combat the Infective Endocarditis.

The impact of Schistosoma haematobium infection and of praziquantel treatment on the growth of primary school children in Bertoua, Cameroon.

Our objective was to determine in a Cameroonian school population the effect of mild to moderate S. haematobium infection intensity on growth and development of children before and 6 months after praziquantel treatment. Previous studies have yielded contradictory results. Children from Bertoua schools were divided into four study groups: heavily infected (> 500 eggs 10 ml-1), moderately infected (1-499 eggs 10 ml-1) treated with praziquantel, a similar group treated with placebo, and an uninfected control group. Anthropometric measures--height for age per cent median (HAPM), and weight for age per cent median (WAPM)--were significantly higher among the uninfected children. Stepwise regression analysis showed that S. haematobium and Ascaris infections were the strongest predictors of the HAPM with hookworm and malaria infections playing a lesser role. Post treatment comparison of the praziquantel treatment group and the placebo group showed no significant differences for the anthropometric indicators except for mid-arm circumference. Longer observations of growth after treatment as well as monitoring of the rate of reinfection would be necessary to understand better the effect of S. haematobium on growth.

Albendazole in the treatment of onchocerciasis: double-blind clinical trial in Venezuela.

A double-blind clinical trial was conducted in Monagas State, Venezuela to assess the tolerance and efficacy of albendazole in the therapy of Onchocerca volvulus infection. Forty-nine patients (26 treated and 23 controls) received a 10-day course of albendazole (400 mg/day) or a placebo. Consistent with the excellent tolerance observed, albendazole did not kill microfilariae. However, analysis of changes in microfilarial densities (mf/mg of skin) over one year showed that albendazole was active against O. volvulus, presumably by interfering with embryogenesis. The nature, degree, and duration of this effect remain to be determined.

In utero conversion of supraventricular tachycardia with digoxin and procainamide at 17 weeks' gestation.

The earliest reported case of fetal supraventricular tachycardia at 17 weeks' gestation causing hydrops fetalis is presented. Maternal treatment with digoxin and procainamide successfully cardioverted the fetus with resolution of the hydrops. Using this combination, sinus rhythm was maintained until term.

The impact of Schistosoma haematobium infection and of praziquantel treatment on the growth of primary school children in Bertoua, Cameroon

The association between urinary schistosomiasis and anaemia among infected children remains controversial. The purpose of this study was to determine the impact of schistosoma haematobium infection and treatment with praziquantel on hemoglobin levels among male children aged 6-15 years in Bertoua. Urine examination of 2665 children revealed an infection rate of 23.9 per cent. Children with moderate infection were randomly selected into treatment (238) and placebo (198) groups. Among uninfected children; 174 were randomly selected to serve as controls. Malaria; geohelminth infections and hemoglobin levels were determined before and six months after praziquantel/placebo intervention