Lipid metabolic changes in experimentally induced leptospiral infection with serovars australis, canicola and icterohaemorrhagiae.

Changes in lipid fractions were evaluated in young guinea pigs when infected with 1 ml of 7 day old live cultures of leptospira interrogans serovars australis, canicola and icterohaemorrhagiae. Statistically significant elevation in triglycerides, very low density lipoprotein and phospholipid and a significant reduction in high density lipoprotein (HDL) in all the groups was observed. Cholesterol and low density lipoprotein showed ascending trend in icterohaemorrhagiae group, whereas they were normal in other groups. The results suggest that increase in triglycerides, phospholipid and decrease in HDL in a suspected case of leptospirosis may be considered as markers.

An investigation of leptospirosis in a laboratory animal house.

A study was undertaken to investigate the possible involvement of leptospires in causing infection and persistent deaths among albino mice and wistar rats of a laboratory animal house. The serological study revealed that 79.2% of mice, 90% of wistar rats, 71.4% of guinea pigs and 81.8% of rabbits had leptospiral antibodies to one or more of serogroups. Autumnalis predominated in guinea pigs and mice, while Javanica predominated in wistar rats. Rabbits exhibited equal seroprevalence of Autumnalis and Javanica. The animal house workers had 91.0% sero positivity, predominantly Autumnalis while control human group had only 20%. All isolations made from a mice (M2) and six wistar rats (W1, W4, W8 W9, W12 & W13) were serovar javanica and incidentally the isolate from a trapped house rat (R1) also belonged to the same serovar javanica. The house rat was perhaps the source of virulent leptospires for causing infection and mortality among laboratory animals like mice and wistar rats.

Leptospiral antibodies in patients with recurrent ophthalmic involvement.

Leptospiral antibodies could be demonstrated by microscopic agglutination test in 14 of 15 (93%) patients with acute panuveitis and retinal vasculitis in a preliminary study undertaken during the postmonsoon period at Madurai in Tamilnadu, India. The predominant serogroup was Pomona followed by Autumnalis, Australis and Javanica, the titres being between 1:160 and 1:10240. Titres in the normal controls were 1:20 to 1:80 in 8 of 20 mostly to the endemic serogroup Autumnalis. The involvement of leptospires particularly Pomona as a cause of ophthalmic complications in the patients studied is likely.

Tuberculous meningitis in children--clinical profile, mortality and morbidity of bacteriologically confirmed cases.

One hundred and seven cases of tuberculous meningitis were registered as a part of a case-control study during the period 1990-1992. The CSF of all cases was positive for culture and/or smear for acid fast bacilli. Children were examined at the time of admission and at the time of discharge and they were contacted at the end of 1 year. Clinical picture, mortality and morbidity were analyzed. Mortality of children during the first month of illness was 22%. Some of the cases presented as acute neurological illness. We also came across CSF picture with minimal cytological and biochemical changes but with positive culture results.

Intramuscular injection as a provoking factor for paralysis in acute poliomyelitis. A case control study.

In order to identify the role of intramuscular injection (IM) as a provoking factor for poliomyelitis, a case control study as done at the Institute of Child Health, Madras from May 1988 to May 1989. The case was defined as acute poliomyelitis if he had acute asymmetric flaccid paralysis of lower motor neurone type without objective sensory disturbance following a short episode of fever. Controls were taken from children attending outpatient department for fever. Two controls matched for aged and sex were recruited for each case. Recruitment, data collection and clinical examination were done by a single pediatrician. IM injection received within 30 days prior to onset of paralysis or illness was considered to be the risk factor. The total number of cases and controls recruited were 257 and 515, respectively. Among cases, 172 (66.9%) out of 257 and among controls 252 (48.9%) out of 515, received IM injection within one month earlier to onset of paralysis or illness. The overall risk of paralysis, estimated for IM injection, was increased [odds ratio (OR) 2.1 (95% CI, 1.5-3.0)]. The maximum risk for paralysis was observed to be 2 weeks preceding the illness; the ORs for < 7 days was 2.2 (95% CI, 1.6-3.2) and for 7-13 days 3.2 (95% CI, 1.8 to 5.8). The risk of paralysis associated with IM injection was similar for unimmunized and immunized cases (OR 2.4 and 2.2). Multiple injections were not associated with a higher risk of developing paralysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Risk factors for persistent diarrhea among children under 2 years of age. Case control study.

A case control study was done at the Institute of Child Health, Madras, among prospectively recruited children aged 1-23 months to identify the risk factors for persistent diarrhea. Cases were children with diarrhea persisting for > 14 days. Controls were children with acute diarrhea who had recovered within 7 days. Two controls for each case, matched for age were recruited. The total number of cases and controls recruited were 170 and 340. Fifteen risk factors for association with persistent diarrhea were studied. When the factors were adjusted for covariables by logistic regression, only 6 factors were found to be significant, namely, malnutrition (OR 2.9; 95% CI 1.9-4.5), dysenteric stools (OR 2.4; 95% CI 1.3-4.3), indiscriminate use of antimicrobials (OR 2.4; 95% CI 1.6-3.9), associated illnesses (OR 2.1; 95% CI 1.5-3.1), stools > 10/day (OR 1.8; 95% CI 1.2-2.8) and persistence of dehydration (OR 1.4; 95% CI 1.2-1.7). However, when invasive diarrhea was excluded, weight loss during study period became a significant factor. It is concluded that all children with acute diarrhea should be investigated for associated illnesses and treated adequately, indiscriminate use of antimicrobials should be avoided and nutritional support should be provided.

Risk factors for fatal pneumonia: a case control study.

We conducted a case control study to identify the risk factors for death among hospitalized children with acute pneumonia at the Institute of Child Health, Madras. All the 70 patients who died of pneumonia constituted the case--patients and 140 children recovered from pneumonia, selected by systematic sampling, during the same period served as controls. By univariate analysis, the risk factors for death in pneumonia observed were associated illnesses--Odds Ratio (OR) 22.2. (95% confidence interval [CI] 9.8-51.4; p = < 0.001); congenital anomalies--OR 10.4 (2.9-37.8; p = < 0.001); severe pneumonia--OR 4.2 (1.2-14.4; p = 0.09); marasmic status--OR 2.9 (1.5-5.7; p = 0.001); age under 6 months--OR 2.8 (1.3-5.7; p = 0.004); and severity of the pneumonia (lobar versus segmental)--OR 2.0 (0.9-4.5; p = 0.09). By logistic regression analysis the following risk factors were significant--associated illnesses. (51.6; 18-146.9; p = < 0.001); age under 6 months (6.5; 2-20.6; p = < 0.001), marasmic status (5.8; 2.2-15.6; p = < 0.001); and congenital anomalies (3.8; 2.0-7.1; p = < 0.001). These risk factors should be kept in mind by the clinicians for appropriate intervention at an earlier stage to minimize death.

Risk factors for recurrence of febrile convulsions.

A cohort of hundred children with febrile convulsions, in the age group of 3 months to 5 years were followed up prospectively for one year to study the natural course of the illness, and to determine if specific factors would increase the risk of recurrence of febrile convulsions. The risk factors studied were age of onset under one year, long duration of convulsion (more than 15 minutes), family history of febrile convulsion or epilepsy and combination of two or all of the above factors. Four groups of children with different risk factors were followed up for recurrence of convulsion, after the first attack. A group of children without any risk factor was considered as control and they were also followed up for recurrence of convulsions. Though all the groups with the risk factors, showed a trend towards a higher recurrence rate when compared to controls, the difference observed clinically was not significant statistically. This could be due to the small sample size of each group. A larger study could throw light on the predictive value of these risk factors and narrow down the use of long term anticonvulsant prophylaxis.

Regulation of sialyltransferase activity in intestinal segments of rats.

A differential distribution of sialyltransferase (ST) in different regions of intestine has been shown. Jejunum and ileum homogenates from rats showed almost exclusive presence of alpha-2-3 ST (to Gal in Gal beta-1-4GlcNAc and/or to Gal in Gal beta-1-3GalNAc). In contrast, colon homogenates showed the presence of both alpha-2-3 ST (as above) and alpha-2-6 ST. Incubation of intestinal slices in presence of heat-inactivated horse serum (HHS) showed a time- and temperature-dependent secretion of soluble ST into the medium. Both jejunum and ileum slices showed high rates of secretion of alpha-2-3 ST. Colon slices, though rich in alpha-2-6 ST, secreted only alpha-2-3 ST. Colchicine, an anti-mitotic drug, injected into rats caused about 10-fold increase of the serum ST level. Jejunum slices from colchicine-treated rats showed an increased secretion of alpha-2-6 ST, suggesting that intestine undergoes a change in the expression of normal secretion of alpha-2-3 ST to a secretion of alpha-2-6 ST. The secretion of ST from incubated intestinal slices was inhibited by heparin. Certain protein factors (anti-proteases) in HHS bind to heparin-sepharose column and these protein factors are responsible for causing the secretion of ST into the medium. It has also been found that a supernatant fraction of the colon homogenate activated ST. Gel chromatography on HPLC produced 3-4 protein fractions from the colon cytosol and one of this fraction bearing high molecular weight proteins produced the maximum activation of ST.(ABSTRACT TRUNCATED AT 250 WORDS)

Lesions and immune responses produced in hamsters and guinea pigs inoculated with some strains of leptospira.

Pathogenic lesions and immune responses in hamsters and guinea pigs produced by three leptospiral serovars, viz. autumnalis, grippotyphosa, and pomona, and their pool were experimentally studied. Hepatic lesions precede renal localisation. The infections were documented by the demonstration of leptospires and histopathological study. The 2-Me sensitive IgM was responsible for MAT titres in the early immune response.