Abstract. Salmonella enterica serovar Paratyphi B is known to cause either paratyphoid fever or gastroenteritis. Differentiation of Salmonella ser. Paratyphi B into biotype Java (d-tartrate fermenting, dT+) and biotype Paratyphi B (d-tartrate non-fermenting, dT) is important for Salmonella epidemiology. This study applied a PCR approach to differentiate the two biotypes to augment the conventional biochemical method and to determine the antibiograms and genomic diversity of Malaysian S. Paratyphi B. Among 100 strains tested (clinical, 86; non-humans, 14), only two clinical strains were confirmed as biotype Paratyphi B as indicated by both lead acetate test and PCR. Antibiotic resistance rates were as follows: streptomycin 18%, sulphonamides 13%, ampicillin 10%, chloramphenicol 4%, tetracycline 3%, cefotaxime 2%, cefpodoxime 2%, ceftazidime 2%, gentamicin 1% and trimethoprim 1%. None showed resistance towards amoxicillin-clavulanic acid, ceftiofur, ciprofloxacin, nalidixic acid and trimethoprim-sulphamethoxazole. Seven strains showed multidrug resistance towards 3 or more classes of antimicrobial agents. REP-PCR and PFGE generated 32 and 76 different profiles, respectively. PFGE (D = 0.99) was more discriminative than REP-PCR (D = 0.93) and antimicrobial susceptibility test (D = 0.48) in subtyping the strains. Strains isolated 18 years apart (1982 - 2008) from different localities in Malaysia were clonally related as demonstrated by REP-PCR and PFGE, indicating that these strains were stable and widely distributed. In some clusters, strains isolated from different sources (clinical, food and animal) were grouped together. Thus, biotype Java was the most common biotype of Salmonella ser. Paratyphi B in Malaysia. The PCR approach is highly recommended due to its simplicity, specificity and ease of operation. The level of antimicrobial resistance among Salmonella ser. Paratyphi B remained relatively low in Malaysia but the emergence of resistance to cephalosporins is a cause for concern.
Live eels and processed fish products from Malaysia are routinely checked for microbial pathogens before export to Japan. The eels and water from the ponds are screened for Vibrio cholerae and Salmonella spp, whereas the processed fish products are tested for microbial contamination (aerobic plate count), coliforms, E. coil and Vibrio cholerae. Results showed that live eels and water samples were negative for Vibrio cholerae but Salmonella spp were isolated occasionally. Various types of processed fish products had counts below 1.0 x 10(5) whilst coliforms, E. coli and Vibrio cholerae were absent. Records available showed that procedures involved in the production and transportation of live eel, preparation and processing of fish products have resulted in relatively safe food products.
We studied the use of exhaled carbon monoxide (CO) to identify nicotine dependence among adult Malaysian male smokers. We conducted a cross-sectional study among 107 male smoking staff at a university hospital. We measured their exhaled CO using a piCO+ Smokerlyzer and diagnosed nicotine dependence using a Mini-International Neuropsychiatric Interview (MINI). The optimal cut-off value for exhaled CO was determined. The correlation between exhaled CO level and the Fagerstrom Test for Nicotine Dependence (FTND) was also assessed. The mean exhaled CO level among subjects with nicotine dependence (15.78 ppm) was significantly higher than subjects without nicotine dependence (9.62 ppm). The cut-off value used to identify smokers with nicotine dependence was set at 10 ppm (specificity = 0.721, sensitivity = 0.731, positive predictive value = 0.817 and negative predictive value = 0.617). Psychometric properties were stable with various durations of smoking. Exhaled CO correlated positively with FTND scores (Pearson's rho = 0.398, p = 0.01). Our findings show exhaled CO can be used to identify nicotine dependence among adult Malaysian male smokers.
A total of 1,885 blood and stool samples of four main protozoan parasitic infections were retrospectively reviewed from January, 2000 to April, 2004. Eleven of the 1,350 stool samples were shown positive for Cryptosporidium and Giardia infections; one of the 5 cases was clinically diagnosed as gastrointestinal cryptosporidiosis, while 6 cases were giardiasis. In patients with giardiasis, children were among the high-risk groups, making up 66.7% of these patients. The common presenting signs and symptoms were: diarrhea (83.3%), loss of appetite (83.3%), lethargy (83.3%), fever (66.7%), nausea/vomiting (50.0%), abdominal pain (16.7%), dehydration (16.7%) and rigor and chills (16.7%). Metronidazole was the drug of choice and was given to all symptomatic patients (83.3%). For the blood samples, 28 of the 92 peripheral smears for Plasmodium spp infection were diagnosed as malaria. The age range was from 4 to 57, with a median of 32.5 years. The sex ratio (M:F) was 3.6:1, while the age group of 30-44 years was the most commonly affected in both sexes. The majority of patients were foreigners (60.7%) and non-professional (39%). Plasmodium vivax (71%) infection was the most common pathogen found in these patients, along with a history of traveling to an endemic area of malaria (31%). The predominant presenting signs and symptoms were: fever (27%), rigor and chills (24%), nausea/vomiting (15%) and headache (8%). Chloroquine and primaquine was the most common anti-malarial regimen used (78.6%) in these patients. The seroprevalence of toxoplasmosis in different groups was 258/443 (58%): seropositive for IgG 143 (32.3%); IgM 67 (15%); and IgG + IgM 48 (10.8%). The age range was from 1 to 85, with a mean of 34 (+/- SD 16.6) years. The predominant age group was 21 to 40 years (126; 28.4%). The sex ratio (M:F) was 1.2:1. Subjects were predominantly male (142; 32%) and the Malay (117; 26.4%). Of these, 32 cases were clinically diagnosed with ocular toxoplasmosis. The range of age was from 10 to 56 years with a mean of 30.5 (+/- SD 12.05) years. The sex ratio (M:F) was 1:1.7. The majority were in the age group of 21 to 40 years, female (20; 62.5%), and Malay (17; 53%). They were also single (16; 50%), unemployed (12; 37%), and resided outside Kuala Lumpur (21; 65.6%). The more common clinical presentations were blurring of vision (25; 78%), floaters (10; 31%) and pain in the eye (7; 22%). We found that funduscopic examination (100%) and seropositivity for anti-Toxoplasma antibodies (93.7%) were the main reasons for investigation. Choroidoretinitis was the most common clinical diagnosis (69%), while clindamycin was the most frequently used antimicrobial in all cases. Among HIV-infected patients, 10 cases were diagnosed as AIDS-related toxoplasmic encephalitis (TE) (9 were active and 1 had relapse TE). In addition, 1 case was confirmed as congenital toxoplasmosis.
This retrospective and descriptive study was a report on the clinical situation of tuberculosis in diabetic patients, with 1,651 patients recruited. The mean age of TBDM patients was significantly higher than that of non-diabetic patients (p<0.05). Moreover, TBDM patients had a higher ratio of male to female than the other group. The significant proportion of TB appeared to increase steadily with age in diabetic patients compared to non-diabetic ones (p<0.05). However, they showed similarities in terms of sex, race, marital status, present address, and occupation. A higher percentage of pulmonary tuberculosis (91.4%) was shown in the TBDM group. We found that both groups had no differences in the radiological findings, with opacity or cavity of the upper lobe involvement being 89% and 91% in TBDM and non-diabetic groups, respectively. TBDM patients were shown to have more treatment success (33.3%), particularly the pulmonary type of tuberculosis in the longer duration ( 9 months). Further findings demonstrated that a lower proportion of the TBDM group defaulted in their treatment (19.8%) and experienced resistance to anti-tubercular therapy (1.4%) compared to non-diabetics.
In this retrospective study, we investigated 263 foreign patients who were diagnosed as having tuberculosis at the National Tuberculosis Center (NTBC) from January 2001 to December 2002. The age range was 14-72 years, with a mean of 33.3 +/- 9.95 years. The study subjects were predominantly males (60%) and females comprised 40%, where the greater impact of tuberculosis was observed in the young and active ones (up to 34 years of age), than middle-age (up to 54). A significantly higher percentage of these patients were from the Southeast Asian countries (87%) and particularly occurred in single male (47.5%) and married female (71.4%) patients (p<0.05). We also found that tuberculosis was significantly higher in female (50.5%) and male (64%) with smoking laborers (p<0.05). Fever (70%), cough (90.5%) and BCG vaccination status showed a significantly higher percentage in male patients (p<0.05), whereas lymphadenopathy (22%) was found in a significantly higher percentage in females (p<0.05). Overall, pulmonary disease (94.3%) occurred more commonly in males and the pleura (3.2%) was the most common site of disseminated tuberculosis. By contrast, the lymph node (11.4%) and miliary (4.8%) forms were the more common extrapulmonary tuberculosis in females. More males had higher percentage of treatment completed at > or = 6 (38%) and > or = 9 (13.3%) months in pulmonary tuberculosis, whilst, more females showed higher percentage of treatment completed (8.7%) in extrapulmonary tuberculosis. Surprisingly, more women showed non-compliance to the anti-tubercular therapy than their counterpart in this study.
We retrospectively reviewed 205 HIV-infected patients, who came at first entry from January 2001 to December 2002 to the Hospital Kuala Lumpur, Kuala Lumpur, Malaysia. The aged range was 21-69 years [mean 37.25 years (+/- SD) 8.1]. Subjects were mainly in the age group 35-44 years. The majority of patients were male (82%), Chinese (55.1%), single (55.6%), resided in Kuala Lumpur (55.1%), and were unemployed (57.1%). The most frequent routes of transmission were sexual contact (78.5%), followed by IDUs (30%), blood transfusion (5%), and unknown (0.5%). Oral candidiasis was the most common mucocutaneous disease and significant co-existence was found with the main opportunistic systemic diseases, such as TB, PCP, toxoplasmic encephalitis, penicillosis, and CMV retinitis (p < 0.05). In this study, the range of CD4 counts was 0-910, with a median of 35 cells/mm3. Significant associations between a CD4 level less than 100 cells/mm3 at the time of diagnosis, and the occurrence of major opportunistic diseases, such as candidiasis, TB, PCP, TE, herpes simplex infection, CMV retinitis, penicillosis, and histoplasmosis were found (p < 0.05) in this study.
A study was carried out on 49 H. pylori-positive and 11 H. pylori-negative patients to determine the reactivity of peripheral blood lymphocytes (PBL) to phytohemagglutinin (PHA) and acid glycine extract (AGE) of H. pylori, and to identify cells responsible for imunosuppression. Based on response to PHA stimulation, cell-mediated immunity of all patients were competent. In some patients, however, response to AGE of H. pylori was suppressed by plastic adherent cells. This study provided evidence of the presence of plastic adherent suppressor cells which suppressed PBL response to AGE of H. pylori but not to PHA suggesting that immunosuppression is antigen specific. There is also an indication that immunosuppression may be species-specific as PBL devoid of plastic adherent cells only responded to stimulation by AGE of H. pylori but not that to AGE of C. jejuni.
Stool samples from 836 cases with diarrhea and acute gastroenteritis from the Pediatric ward, Penang General Hospital, were examined for Cryptosporidium oocysts. A dimethyl sulfoxide modified acid fast technique was used for the identification of the parasites. 36 samples or 4.3% were found to be positive for Cryptosporidium. The prevalence of infection was higher (2.39%) in children with diarrhea and vomiting than in children with acute gastroenteritis alone (0.8%). Stool examination and cultures from the Cryptosporidium positive samples revealed no other parasites, rotavirus or enteropathogenic bacteria. This suggests that Cryptosporidium may be an important agent in the causation of diarrhea in young children. A routine laboratory examination for the detection of Cryptosporidium in the search for causal agents of childhood diarrhea in our environment may, therefore, be significant.
The objective of this study was to characterize the polypeptides associated with cysts of Blastocystis hominis. This form is believed to be infective and plays a role in parasite resistance to anti-B. hominis drugs currently used for treatment of Blastocystis associated diarrhea. Cysts were induced through in vitro culture of the parasite in complete medium supplemented with bacterial extract with trypticase, metronidazole or doxycycline. SDS-PAGE analysis showed almost similar polypeptide patterns of parasite extracts obtained from in vitro cultured parasites before and after exposure with the three supplements. Polypeptide bands at 76, 58.5, 48, 45, 40, 38, 32, 25 and 22 kDa were constantly seen in all antigenic preparations and no specific cyst-associated polypeptide was present. However, on immunoblot analysis, 3 out of 16 blastocystosis human sera identified a cyst-associated polypeptide at 60 kDa in all parasite extracts prepared from cultures with the three supplements. In addition, there were associated morphological changes detected in these parasites stained with acridine orange and observed under fluorescence microscopy. Metronidazole induced cyst forms (reddish cells) as early as 12 hours post-exposure; more cyst production (with stronger immunoblot bands) occurred after 24 hours exposure. However, cysts rupture with release and destruction of B. hominis daughters cells occurred after 48 hours exposure. Doxycycline induced less cyst-like forms at 24 hours (weaker 60 kDa band) and less destruction of the cysts (60 kDa band still present at 72 hours post exposure). Bacterial extract and trypticase also induced cysts at 12 hours with increasing numbers up to 72 hours exposure (corresponding increase in intensity of 60 kDa band from samples harvested at 12 to 72 hours post exposure) without any sign of deleterious effect on the parasite.
Faecal samples from patients admitted to the District Hospital in Balik, Pulau, Penang revealed high infection rates for Ascaris lumbricoides, Trichuris trichiura and hookworms. The prevalence rates were Trichuris trichiura 51.7%, Ascaris lumbricoides 31.9% and hookworm 37.2%. The overall highest infection is among the Malays (79%), the least being among the Chinese (61.1%). The prevalence of Ascaris lumbricoides was highest in the 11-20 age group. The prevalence of Trichura was highest in the 51-60 age group, Ascaris and Trichuris infections is higher among the males but hookworm infection is higher among the females. 72.6% of the patients were infected with at least one type of helminth and 32.9% of the patients were infected with at least 2 types of helminths.
Using ELISA and COPT diagnostic tests, serological evidence of Malaysian schistosomiasis was discovered among Orang Asli populations from three areas in Peninsular Malaysia. Serum samples collected in 1975 indicated an ELISA-positive prevalence of 25% and a COPT prevalence of 11% from Pos Iskandar, Pahang and an ELISA prevalence of 13% and a COPT of 4% from Bukit Lanjan, Selangor. Resurveys at these site in 1982-1984 showed a continued presence of serological positive individuals but prevalence rates were markedly lower: 7% and 1% for ELISA and 4% and 2% for COPT at Pos Iskandar and Bukit Lanjan respectively. Snail hosts were not found at either site. The source of infection for persons living in these lowland areas remains unknown. In a third area, Kuala Tahan, Pahang, located in the foothills of the central mountain range, foci of transmission have been found near to Orang Asli settlements. The serological prevalence rate among Negrito Orang Asli in that study area was 9% for ELISA and 4% for COPT. Thirty-three of 36 COPT-positive sera produced vacuolated bleb precipates and in 31 these were the only reactions seen. The high percentage of positives producing only these precipates suggests that among Orang Asli schistosomiasis patients such reactions are not an indication of recently acquired infection as has been reported for schistosomiasis patients in the Philippines.
During 1984-1985, a total of 838 sera obtained from individuals of different age groups, mostly blood donors and those whose sera were received for VDRL tests and other serological investigations. The sera were titrated for complement fixing antibodies against cytomegalovirus (Ad169 strain). Three hundred and fifty two (41%) out of 838 sera showed significant antibody titre. The incidence of this virus infection varied form 26% in the age group of 11-20 years to 59% of those above 50 years of age. Geometric mean titre (GMT) was highest (22) in age groups of 11-20 years and those over 50 years indicating active viral infection in these two age groups. GMT was also significantly higher in females in all age groups except in the age group of 21-30 years and those above 50 years, indicating that active viral infection is more common in females.
The risk behavior in malaria has been identified as one of the factors contributing to malaria in Malaysia. The occurrence of malaria among illegal immigrants and indigenous groups, staying in risk prone areas where conditions are favorable for transmission, highlights the behavior pattern of these groups. In these areas the usual anti-malarial activities are less effective and thus there is a need to identify control measures suited to that particular condition and environment and to community groups. Some of the determinants contributing to the increase in malaria cases like man-vector contact, non-compliance to drugs, complications of the disease, and factors interfering with malaria control measures, factors favoring transmission and proposals to modify risk behavior, which can be applied in an endeavor to control the diseases, have been discussed.
Melioidosis is endemic in Malaysia. Cutaneous melioidosis is one manifestation and it may progress to necrotizing fasciitis. The case highlights a 46-year-old male, a chicken-seller who presented with scalp cellulitis which later progressed to necrotizing fasciitis and pneumonia are presented here. It illustrates several key features of the presentation, prompt laboratory diagnosis and early treatment of melioidosis which saved the patient's life.
A cross-sectional survey of the nutritional status of children aged 1-10 years old from the Kuala Betis resettlement villages was carried out. A total of 620 children were examined, of which 329 were preschool children and 291 were schoolchildren. The age was determined and anthropometric measurements such as weight, height and MUAC were taken. The nutritional status was assessed by looking at the distributions of the z-scores of weight-for-age (WAZ), height-for-age (HAZ) and weight-for-height (WHZ) in relation to the growth charts of the National Center for Health Statistics reference population. It was found that the nutritional status of the Orang Asli children was poor, with a prevalence of 33.7-65.3% underweight, 55.3-74.4% stunting and 4.4-29.7% wasting based on the NCHS reference values. The prevalence of malnutrition among the Malay children was lower, underweight--7.3-34.1%, stunting--9.8-34.1% and wasting--1.7-17.1%. The nutritional status of the Orang Asli children were poorer compared to the Malay children. More preschool Orang Asli children were stunted compared to the Orang Asli schoolchildren. This may be due to the poor economic base of the Orang Asli community during the transformation period after resettlement. A comprehensive primary health care program is essential, especially targeting the preschool Orang Asli children in these resettlement villages.
The effect of infection with teratogenic viruses at early stages of pregnancy is not fully understood. This study aimed to look at the effect of infection with teratogenic viruses such as bovine viral diarrhea virus (BVDV) and border disease virus (BDV), on early stage embryos at the hatched blastocyst stage. BVDV and BDV are known to cross the placenta of infected mothers and lead to congenital defects and death of developing fetuses. This study can be a good model for better understanding the effects of other teratogenic viruses such as Rubella virus in humans.
Reciprocal and homologous mating experiments between Malaysian Aedes aegypti and Aedes albopictus mosquitoes were conducted in the laboratory. Two methods were employed, namely an artificial mating technique and a natural cage mating technique. The study demonstrated there exists a strong reproductive isolation between Ae. aegypti and Ae. albopictus. Insemination occurred in cross-mating experiments between Ae. aegypti females and Ae. albopictus males and also between Ae. albopictus females and Ae. aegypti males. Cross mating between Ae. aegypti females and Ae. albopictus males produced more eggs than that between Ae. albopictus females and Ae. aegypti males with both artificial mating and natural cage mating techniques. The matings did not result in the production of viable eggs by the females. No embryonation of these eggs was observed when the eggs were bleached. With homologous mating Aedes aegypti produced significantly greater numbers of eggs compared to Aedes albopictus mosquitoes, and all the eggs hatched successfully.
A prospective cohort study was conducted to determine the incidence of progressive encephalopathy (PE) and its associated clinical manifestations amongst a cohort of HIV infected children attending the HIV/AIDS clinic of the Pediatric Institute, Kuala Lumpur Hospital, Malaysia. Neurological and neurobehavioral assessments were performed in 55 children with HIV over a 24-month study period. Parameters assessed were physical and neurological assessments, CD4 counts, CD4 percentages, RNA viral loads and an IQ assessment at four monthly intervals. PE was diagnosed when patient developed at least one of the definitive criteria for PE based on the Consensus of Pediatric Neurology/Psychology Working Group, AIDS Clinical Trial 1996. The incidence of encephalopathy was 18.2% (n = 10) in 2002. All the patients had hepatosplenomegaly, lymphadenopathy, abnormal deep tendon reflexes and five had impairment in brain growth. The CD4 counts and CD4 percentages were more likely to be associated with PE compared to the non-PE group.