A total of 320 faecal specimens obtained from 295 patients (192 children and 103 adults) with diarrhoea and 47 faecal specimens from healthy adults were screened for Cryptosporidium oocysts. Faecal specimens were first screened by modified Ziehl Neelsen stain and specimens with oocysts were confirmed by direct immunofluorescence technique. Cryptosporidium oocysts were detected in 4 children but not in normal healthy adults or in diarrhoeic adults.
The VP4 genetic groups of 151 field strains of human rotaviruses obtained from infants and young children with diarrhea from four locations in Malaysia were analyzed. The strains were adapted to growth in tissue culture and studied further by molecular hybridization of northern blotted RNA to PCR-generated cDNA probes representing amino acids 84-180 of the KU strain VP4, 83-181 of the DS-1 strain VP4, and 83-180 of either the 1076 or K8 strain VP4, representing VP4 genetic groups 1-4 (P1A, P1B, P2, and P3), respectively. The majority (79% of the field strains hybridized with the KU VP4 genetic group 1 probe and were associated with G1, G3, G4, untypable, or mixed G serotypes. VP4 genetic group 1 (P1A) strains were the most common in all locations in Malaysia between 1978-1988. Three strains which exhibited G3 and subgroup I specificity hybridized with the K8 VP4 genetic group 4 probe. These three VP4 genetic group 4 (P3) strains were detected in two different years and locations, extending the initial detection of this VP4 genetic group (the K8 strain) in Japan to a larger geographical area of Asia.
Congenital chloride diarrhoea is a rare disorder mainly reported in Finland. A Malay child with congenital chloride diarrhoea presenting at six months of age with watery stools from birth and failure to thrive is reported.
Stool specimens from 334 infants and young children hospitalized with diarrhea in the General Hospital, Kuala Lumpur, Malaysia between August and November, 1987 were analyzed for the presence of rotavirus double-stranded (ds) RNA by polyacrylamide gel electrophoresis. Of the 334 specimens analyzed, 32 (9.6%) were positive for rotavirus RNA. One specimen (designated G147) exhibited a ds RNA electropherotype profile characteristic of Group C rotavirus and was selected for further characterization. In Northern blot hybridization studies, the gene 5 segment of strain G147 hybridized with a cDNA probe generated from the cloned gene 5 (which encodes the VP6 inner capsid protein that is group specific) of porcine Group C rotavirus strain Cowden, confirming the classification of strain G147 in Group C. The association of Group C rotavirus with diarrheal illness in Malaysia is consistent with earlier studies that suggest a global distribution of this virus and supports the need for additional epidemiologic studies.
Approximately 57% of clinical and 33% of poultry isolates examined produced a cytotoxin. Cytotoxic activity was detected in 25 (50%) isolates of Campylobacter of which 12 were isolated from bloody diarrhea and 9 from watery stools. The cytotoxin titers were low, ranging from 2 to 16. The crude filtrates from 50 Campylobacter isolates showed no cytotoxic effect in Vero cells, no fluid accumulation in suckling mice and no hemolytic activity.
Blastocystis hominis has long been described as a non pathogenic protozoan parasite until recently when claims have been made that it can result in pathogenic conditions. Of the 729 stool samples (614 from survey and 115 from pediatric wards) examined, 18.1% of them were found to be positive for one or more intestinal protozoan cyst. The commonest was Giardia intestinalis (8.4%) Followed by Entamoeba coli (7.1%) and Entamoeba histolytica (5.1%) in the normal children without symptoms of diarrhea. When diarrheic stools were examined, the commonest parasite encountered was Giardia (20.4%), followed by E. coli (15.9%) and E. histolytica (9.7%). Blastocystis was observed in 4.4% of the children who had diarrhea and 1.1% among the children taken from the normal population in the rural areas.
A retrospective histological analysis of colonic biopsies received by the Department of Pathology, University of Malaya during the 4-year-period between 1990 and 1993 revealed nine cases of microscopic colitis (MC). The ages of the patients ranged from 18 to 53 years. Seven patients were females with a female to male ratio of 3.5 :1. The main clinical symptom was chronic diarrhoea of duration varying from 4 months to 5 years. None of the patients had any systemic illness or were on any prior medication. Colonoscopy and barium enema observations in all the subjects were essentially normal. Colonic biopsies showed diffuse plasmacytic infiltration of the lamina propria, intraepithelial lymphocytic infiltration and normal crypt pattern. To the best of our knowledge, this is the first documented report on MC from Malaysia. It is envisaged that better recognition of this condition by histopathologists would reduce the numbers in the often diagnosed category of "nonspecific colitis".
A 16-year-old female from Rantau Panjang, Kelantan reported having diarrhoea for three months. During this period, she lost 15 lb in weight and was treated with antibiotics and anti-spasmodic tablets with no improvement. Stool examinations by private laboratories revealed "worm-like eggs". She was treated for worms with mebendazole which helped to reduce the symptoms but not completely. The patient continued passing out the abnormal "worm-like eggs" which were later identified as pollen grains.
The relative efficacy and incidence of hypernatremia of a rice starch based low sodium (sodium of 60 mmol/L) oral electrolyte solution was compared to the standard WHO oral rehydration solution (ORS; sodium 90 mmol/L) in 60 infants with non choleragenic acute diarrhoea. Both solutions were found to be equally effective in correcting dehydration as determined by the respective post hydration weight gain which was 150 +/- 175 gms in the rice starch low sodium ORS group and 164 +/- 125 gms in the standard WHO ORS group. However, the mean frequency of stools was greater and the duration of stay longer in the WHO ORS group compared to the rice starch low sodium group. There were 5 cases of hypernatremia in the WHO ORS group as opposed to only one in the rice starch low sodium ORS group. The present study shows that a rice starch low sodium ORS was as effective as the standard WHO ORS and had a lower incidence of hypernatremia in the fluid and electrolyte management of infants with non choleragenic diarrhoea.
Enterokinase has a critical role in initiating proteolytic digestion by hydrolysing the conversion of pancreatic trypsinogen into trypsin. The enzyme is synthesised by enterocytes of the proximal small intestine and initially incorporated into the brush border from where it is released into the intestinal lumen by the action of pancreatic secretions. The aim of the study was to analyse enterokinase activity in the duodenal mucosa of infants with diarrhoeal disease including cow's milk protein-sensitive enteropathy. Our observations show that the mean depletion of enterokinase was only 17% compared to 60-80% for other brush border enzymes like disaccharidases, peptidases and alkaline phosphatases in infants with diarrhoea. This suggests that enterokinase activity in the small bowel enteropathies may be dependent not only on the degree of mucosal damage specifically but also on the extent of damage to the goblet cell population where the enzyme is synthesised. Thus the enterokinase activity was reduced in acute and chronic diarrhoea with marked mucosal damage where significant reduction of goblet cell population was evident but the enzyme was relatively little affected when the mucosa was damaged mildly.
The production of heat-labile (LT) and heat-stable (ST) enterotoxins, colonisation factor antigens (CFAs) and haemagglutinins was investigated amongst 310 Escherichia coli (E. coli) isolates obtained from 62 children under the age of five, with diarrhoea. Twenty-one isolates were found to produce enterotoxins, of which fifteen (71%) isolates produced ST only, 2 (10%) produced LT only and 4 (19%) produced both LT and ST. However, none of the isolates demonstrated any of the common CFAs identified to date, but 8 out of the 21 isolates demonstrated haemagglutination with rabbit, sheep or human group A erythrocytes, suggesting the presence of putative CFAs, yet unidentified.
Aichi virus was isolated in Vero cells from 5 (2.3%) of 222 Pakistani children with gastroenteritis but none was found in 91 healthy children. Aichi virus was also isolated from 5 (0.7%) of 722 Japanese travelers returned from tours to Southeast Asian countries and complained of gastrointestinal symptoms at the quarantine station of Nagoya International Airport in Japan. Of 5 Japanese travelers, 3 were returning from Indonesia, and 2 from Thailand or Malaysia. These results indicate that Aichi virus or a similar agent is endemic in Southeast Asian countries and is a cause of gastrointestinal symptoms in children in these areas or in Japanese travelers who visit there.
By means of the gentamicin HEp-2 cell invasion assay, it was demonstrated that 82% of the Campylobacters tested were cell-invasive, including 83% of isolates from bloody diarrhoea and 80% of isolates from watery diarrhoea. The large number of invasive strains from watery diarrhoea suggests the possible role of invasiveness in the production of watery diarrhoea. Whether this stage can progress further to more severe symptoms such as bloody diarrhoea remains to be elucidated. Whether this progression to bloody diarrhoea occurs as a result of toxin production is still debatable. In Vero cells, invasion was less efficient and intracellular multiplication was not observed.
A review of all colonic biopsies received by the Department of Pathology during a 8-year period revealed 41 cases of ulcerative colitis (UC). The diagnosis was based on histological and clinical features. The age range of patients was between 14 - 76 years with a median age of 35.4 years. The disease was more prevalent among Indians. The common presenting sysmptoms were diarrhoea (100%) and haematochezia (83%). The extent of colonic involvement varied. Twelve patients (29.2%) had pancolitis and 8 (19.5%) had proctitis.Extraintestinal manifestations were rare and only one patient had pyoderma gangrenosum. One patient developed multifocal colorectal cancer 10 years after the inial diagnosis of UC and died 2 years later due to metastases. Histology plays an important role in the diagnosis and management of patients with UC. We noted a good correlation between clinical and pathological features. The most recent colonic biopsy showed features of chronic UC with activity in 34 cases and features of remission in 4 cases.
A 57-year-old man, while on travel in Malaysia, suffered from diarrhea after he ate fruits. He developed limbs weakness without sensory disturbance after his return to Japan. Serum from the patient had high IgG anti-GM1 antibody titer. Campylobacter jejuni was isolated from his stool. The serotype belonged to PEN 5. The patient received double-filtration plasmapheresis 7 times during from days 6 to 17. Muscle strength began to recover gradually on day 10, and returned to normal 5 months after the onset of neurologic symptoms. Repeated neurophysiologic studies indicated that the axonal degeneration of motor nerves was predominant process. This case suggests that Guillain-Barré syndrome is a complication of traveler's diarrhea.
Amongst 107 diarrheal cases studied a bacterial agent was isolated from 71 (66%) cases of which 60 (85%) were due to a single agent and the remaining 11 (15%) were of mixed infections. Enterotoxigenic Escherichia coli (ETEC) was isolated from 65 cases. Other pathogens isolated included Salmonella spp, Shigella spp and rotavirus. There was a higher isolation rate of ETEC from females and rotavirus from males. The infection rate was found to higher for the 0-2 year age group as compared to the 3-5 year age group. Amongst the ETEC isolated the STa 2 toxotype was the predominant type.
Abdominal tuberculosis (TB) is common. But the diagnosis of abdominal TB is fraught with difficulties as it is often not possible to get a microbiological confirmation of the infection. We therefore undertook this study to highlight those pertinent clinical and laboratory features which would enable one to make a provisional diagnosis of abdominal TB early, to pave way for a trial of anti-tuberculosis chemotherapy.
Aeromonas hydrophila strains obtained from diarrhoeal samples of human patients (19 isolates) and freshwater ponds (11 isolates) were analysed for siderophore production. Both clinical and environmental isolates showed significantly increased siderophore production under iron-limiting conditions both at 28 degrees C and at 37 degrees C. Clinical isolates consistently produced higher levels of siderophores than did the environmental isolates. The role of plasmids in moderating siderophore production was studied after curing with acridine orange. Treatment with acridine orange for 24 h removed the larger plasmids but the smaller plasmids (< 5 MDa), more common in the environmental isolates, were resistant to curing. As found in the untreated isolates, the cured clinical isolates produced higher mean levels of siderophores than the cured environmental isolates. Siderophore production in A. hydrophila was significantly influenced by iron-limiting cultural conditions and the source of isolates, but plasmid content and growth temperature at 28 degrees C or 37 degrees C had little effect on production. The basis for the greater production of siderophores in clinical isolates than in environmental isolates needs further study.
A blocking test was incorporated into the commercial IDEIA Adenovirus test (DAKO Diagnostics Ltd., Cambridgeshire, UK) to detect false positive results when faecal specimens were tested for adenovirus antigen. Immune rabbit serum raised against pooled adenovirus particles from human faecal specimens, together with the pre-immune serum, was used. Assessment of positive showed that false positives were produced under two different conditions: when results were based on visual determination instead of a cut-off value determined from photometric reading, and when absorbance values were not immediately read at the end of the test. Under the optimum condition for reading and assessment of test results (immediate reading and photometric determination), 11% of 65 adenovirus-positive samples were checked by the blocking ELISA as false positives. The rest of the specimens showed blocking of positive absorbance values by 70 to 98%. ELISA was found to be more sensitive than immune electron microscopy on samples with lower antigen concentration.