Sexually-transmitted disease (STD) markers in multitransfused children in relation to human immunodeficiency virus type-1 (HIV-1) infection: impact of STD markers in blood donors

Association of serological markers for various sexually transmitted diseases (STDs) with Human Immunodeficiency Virus type 1 (HIV-1) infection among heterosexually promiscuous blood donors is well recognized. However, possibility of similar association among children receiving transfusion from these donors has not been adequately explored. Study on the association of some STD markers with HIV-1 infection in multitransfused (MT) children showed that both HIV-1 positive and HIV-1 negative groups of children had significantly higher prevalence of hepatitis B virus (HBV) markers, i.e. HBsAg (23 and 30 per cent), anti-HBs (46 and 57 per cent), anti-HBc (18 and 23 per cent), antibodies to cytomegalovirus of IgM class (36 and 37 per cent) and IgG class (72.7 and 70 per cent), IgG antibodies to Herpes Simplex Virus type-2 (23 and 23 per cent) compared to control group. However, seropositivity for HIV-1 infection could not be attributed as a risk factor for any of these markers in the group of MT children. On the contrary, significant association of anti HBc, anti HCV, CMV IgG and antitreponemal antibody with HIV-1 infection could be recorded in the group of blood donors. It appeared that due to low prevalence of HIV-1 infection among blood donors in India, both HIV-1 positive and HIV-1 negative groups of MT children received transfusion from HIV negative donors predominantly resulting in a comparable prevalence of STD markers in both the groups of MT children due to cumulative effect of transfusion from HIV-1 negative donors.

Identification of a contiguous 6-residue determinant in the MHV receptor that controls the level of virion binding to cells

Murine carcinoembryonic antigens serve as receptors for the binding and entry of the enveloped coronavirus mouse hepatitis virus (MHV) into cells. Numerous receptor isoforms are now known, and each has extensive differences in its amino terminal immunoglobulin-like domain (NTD) to which MHV binds via its protruding spike proteins. Some of these receptor alterations may affect the ability to bind viral spikes. To identify individual residues controlling virus binding differences, we have used plasmid and vaccinia virus vectors to express two forms of MHV receptor differing only in their NTD. The two receptors, designated biliary glycoproteins (Bgp) 1a and 1bNTD, varied by 29 residues in the 107 amino acid NTD. When expressed from cDNAs in receptor-negative HeLa cells, these two Bgp molecules were displayed on cell surfaces to equivalent levels, as both were equally modified by a membrane-impermeant biotinylation reagent. Infectious center assays revealed that the 1a isoform was 10 to 100 times more effective than 1bNTD in its ability to confer sensitivity to MHV (strain A59) infection. Bgp1a was also more effective than Bgp1bNTD in comparative virus absorption assays, binding 6 times-more MHV (strain A59) and 2.5 times more MHV (strain JHMX). Bgp1a was similarly more effective in promoting the capacity of viral spikes to mediate intercellular membrane fusion as judged by quantitation of syncytia following cocultivation of spike and receptor-bearing cells. To identify residues influencing these differences, we inserted varying numbers of 1b residues into the Bgp1a background via restriction fragment exchange and site-directed mutagenesis. Analysis of the resulting chimeric receptors showed that residues 38 to 43 of the NTD were key determinants of the binding and fusion differences between the two receptors. These residues map to an exposed loop (C-C' loop) in a structural model of the closely related human carcinoembryonic antigen.

Multi-resistant Staphylococcus haemolyticus in a neonatal unit in New Delhi

We describe a cluster of infections in a neonatal nursery due to an infrequently reported staphylococcal species, Staphylococcus haemolyticus. S. haemolyticus resistant to penicillin, methicillin, gentamicin, erythromycin, chloramphenicol and tetracycline (PMGECT) was isolated from a series of infections in neonates (conjunctivitis 6, blood 2, pustules 2) over a period of 3 weeks in a neonatal nursery. Surveillance cultures from 22 neonates, their mothers in an adjacent maternity ward and staff revealed that S. haemolyticus with three resistance patterns (PMGECT, PMG and PME) was circulating in the unit. It was isolated from two caesarian wounds, the nose/ear/umbilicus of six asymptomatic infants and from the noses of three mothers and one nurse. S. haemolyticus showed a higher frequency of resistance to antibiotics than Staphylococcus aureus and Staphylococcus epidermidis isolated from the unit at the same time. Local and asymptomatic infections were treated with local neosporin application whereas netilmicin was used to treat systemic infection. Infections were controlled by emphasising the importance of handwashing, asepsis and eye care.

Wegener's presenting as submandibular swelling

We describe a patient in whom bilateral swelling of submandibular glands was the initial manifestation of limited Wegener's disease. The diagnosis was based on positive anti-neutrophil cytoplasmic antibody [C-ANCA], dense inflammatory infiltrate predominantly of lymphocytes in submandibular glands, presence of non-caseating ill-formed granulomas in transbronchial biopsy and resolution of symptoms following immuno-suppressive treatment.

Profile of antigen-specific antibody response detectable by western blot in relation to diagnostic criteria for human immunodeficiency virus type-1 (HIV-1) infection

BACKGROUND

Variability in the profile of antigen-reactive bands in Western blot for serodiagnosis of human immunodeficiency virus (HIV) infection may result in disagreement regarding interpretation of positive result, due to lack of consensus in the interpretive criteria laid down by various organisations.

OBJECTIVES

The objectives of this study were (i) to find out the extent of disagreement over various criteria regarding interpretation of positivity in Western blot and (ii) to review the discordance by retesting the discordant specimens using recombinant antigens as well as by performing repeat Western blot in follow-up specimens.

STUDY DESIGN

A total of 467 specimens from high-risk groups, diagnosed positive for HIV type-1 (HIV-1) infection by the criteria of at least one of the five organisations, viz. Association of State and Public Health Laboratories Directors (ASTPHLD), Consortium for Retrovirus Serology (CRSS), American Red Cross (ARC) and World Health Organisation (WHO), were analysed to find out the extent of discordance between various criteria for interpretation of Western blot positivity. The discordant specimens were subjected to line immunoassay (LIA) using recombinant antigens. Also, follow-up Western blots were performed in case of discordant specimens at 6, 12 and 24 weeks intervals.

RESULTS

We observed that criteria laid down by ASTPHLD, CDC and CRSS scored all the specimens as positive while ARC and WHO criteria scored 13 (2.8%) and 18 (3.8%) of specimens, respectively, as negatives which were detected as positives by other criteria (discordant specimens). The gp41 reactive band was the most frequently missing band, being undetectable in 11.6% of specimens while bands reactive to p24, p31, gp120 and gp160 could not be recorded in 1.9%, 9.4% and 3.2% and 1.5.% of specimens, respectively. Testing of the discordant specimens with recombinant antigen preparation and with repeat Western blot in follow-up specimens collected at 6, 12 and 24 weeks demonstrated all bands undetectable in initial Western blot, except 25% of gp41 reactive bands.

CONCLUSIONS

It is felt that before selecting any criterion for Western blot positivity, it should be evaluated in the local population at risk for HIV-1 infection with additional or follow-up tests.

Non Hepatitis viruses in causation of acute sporadic non-A, non-B viral hepatitis

Viruses other than Hepatitis viruses i.e. Cytomegalovirus, Epstein-Barr Rubella etc., can cause a clinical picture resembling that of viral hepatitis. Consequently, these viruses can falsely contribute to the diagnosis of Non-A, Non-B hepatitis amongst of sporadic jaundice. This study attempts to find out the possibility of occurrence of such an event.

Further evaluation of alternative strategy for HIV testing in India

A total 320 sera from groups at risk for HIV were evaluated by two (198 specimens) or three (122 specimens) screening tests for confirmatory anti-HIV testing in comparison to Western Blot as gold standard. Sera positive by both screening tests showed 100% correlation with Western Blot although with a false positivity rate of 3.2%. In specimens positive by 1st screening test but negative by the second, (considered negative for anti-HIV antibody as per WHO algorithm), 8.7% were found to be Western Blot positive showing the serious problem of false negativity of the proposed WHO algorithm. Employing the system of three screening test systems did not provide additional benefit for the specimens positive by initial two screening tests since all of them were positive by third test also. However, the study involving three screening tests substantiated the need for Western Blot in discordant specimens (i.e. positive by first test but negative by second), since in this group one out of 22 (4.6%) such specimens were Western Blot positive. Considering the serious consequences of both false positive and false negative results, it is felt that alternative strategy of confirmatory anti-HIV serology, although economical may not be suitable substitute for Western Blot in India at this juncture when the prevalence of HIV infection is relatively low.

Virologic surveillance of poliomyelitis in Delhi

OBJECTIVE

Virologic surveillance of poliomyelitis to monitor the transmission of wild polio virus in the community.

STUDY AREA

All major hospitals of Delhi and surrounding area.

METHODS

Stool samples were collected from 1221 cases of acute flaccid paralysis during 1992-1994 and were subjected to virus isolation on RD and HEp2 cell line. Viruses isolated were analyzed further by microneutralization test using polio and nonpolio antisera. The polio isolates were further characterized as vaccine or wild type using ELISA and probe technology.

RESULTS

Out of the 1221 cases tested, virus was isolated in 57.4%. Among the virus positive cases, polio was isolated in 57% and in 43% non polio entero viruses were detected. The most prevalent was polio virus type 1. Most of the strains were wild type.

CONCLUSION

Wild polio virus was prevailing in the community under study between the years 1992-1994.

Current status of Takayasu arteritis in India

The clinical features of 106 patients of Takayasu arteritis (TA) seen over a period of 16 years are documented (65 females and 41 males). The mean age was 27.3 +/- 9.2 years. Hypertension was the commonest mode of presentation (51.3%) and was detected in 82 patients (77.4%) at the time of presentation. Vascular bruits were heard in 72 patients (67.9%) and 13 patients (12.3%) were in congestive heart failure. Aortography was performed in 95 patients. Based on the extent of involvement, Type I (branches of aortic arch) was seen in 7 (6.6%) patients, Type II (aortic arch, its branches and descending thoracic aorta) in 7 (6.6%) patients, Type III (descending thoracic aorta and abdominal aorta) in 4 (3.8%) patients, Type IV (abdominal aorta only) in 29 (27.3%) patients and Type V (aortic arch, descending thoracic aorta and abdominal aorta) in 59 (55.7%) patients. Therapeutic modalities included antihypertensive drug therapy in 81 patients, antitubercular drugs in 8 patients, steroids in 16 patients and cyclophosphamide in one patient. Response to steroids was satisfactory in 5 of these 16 patients while the lesions of vasculitis healed in the patient who was treated with cyclophosphamide. Surgical interventions included nephrectomy and autotransplantation of kidney in 3 patients each and revascularization in 4 patients and angioplasty in 4 patients. In the area of pathogenesis of this disease, a high activity of protein kinase C(PKC), an increased intracellular calcium and inositol 1,4,5 triphosphate in both unstimulated and stimulated T cells of TA was observed. These findings suggest an activation of PKC-calcium pathway in TA.

Alteration of peripheral blood lymphocyte subsets in essential hypertension

OBJECTIVE

To assess lymphocytic subpopulation by labelled monoclonal antibody technique in a small group of patients with untreated essential hypertension (EH) and to detect any alteration with control of blood pressure.

DESIGN

Prospective study with phenotypic estimation of lymphocytes at presentation and a minimum of two weeks after the control of blood pressure.

SETTING

Referral, tertiary care hospital.

PATIENTS

Group 1, normotensive controls (n = 10); group 2, mild to moderate essential hypertension (n = 10); group 3, severe (accelerated/malignant) hypertension (n = 10). All the secondary causes of hypertension were ruled out by a thorough history, physical examination and appropriate radiological and biochemical investigations.

TESTS

Venous blood samples, taken at entry and a minimum of two weeks after control of blood pressure, were analyzed by alkaline phosphatase antialkaline phosphatase (APAAP) antibody technique for CD4, CD3, CD8 and CD22. Peripheral lymphocytes were separated and cocultured with phytohemagglutinin (PHA) for 72 h and assayed for CD25 by the APAAP technique.

MAIN RESULTS

In untreated patients with EH (groups 2 and 3), there was a significant down regulation of CD3, and CD4 lymphocytes whereas the proportion of mature CD22 cells increased. In group 3 there was a significant down regulation of CD25 with PHA stimulation. A negative correlation was observed between CD25 and diastolic pressure upon pooling the results of groups 2 and 3. No significant alteration in these parameters was observed following control of blood pressure with drugs for up to two weeks.

CONCLUSION

In this small group of patients with untreated EH, a significant alteration in the lymphocytic repertoire was observed. Whether this will be found in large groups of hypertensives remains to be seen.

Hepatitis B--potential of perinatal transmission in India

To estimate the frequency of perinatal hepatitis B virus (HBV) infection, 850 pregnant females were tested for HBsAg and HBeAg using RPHA kits. Frequency of HBsAg positivity was 4.6% by RPHA and 6.34% by micro-ELISA. HBeAg was detected in 18% of the HBsAg positive pregnant females. Presuming a perinatal HBV infection rate of 90% amongst infants born to HBsAg and HBeAg positive pregnant females and 17% amongst infant born to HBsAg positive but HBeAg negative mothers, we estimated that 1.17% to 1.64% infants out of 24 million births occurring annually in this country would be infected with HBV. In other words every year 2.8 to 3.9 lakh infants are being infected by HBV perinatally, 90% of whom will eventually develop chronic HBV infection. Urgent control measures are necessary to circumvent this problem.

Low prevalence of human immunodeficiency virus type-1 (HIV-1) infection in population attending a major hospital in New Delhi, India

During 4 year period between April 1990 and March 1994, 4120 specimens from the patients attending out patient departments of Medical, Surgical and Antenatal units of a major city hospital were tested for HIV infection as a part of an on-going sentinel surveillance programme. In addition, 1440 specimens from the patients attending STD clinic of the same hospital and 862 females seeking termination of pregnancy from a near by hospital were included for comparison. It was found that only 3 individuals with high risk behaviours out of 2002 females attending antenatal clinic showed evidence of HIV infection (rate 1.49 per 1000). The corresponding rate for the group of patients attending STD clinic and seeking termination of pregnancy were 3 out of 1440 (rate 2.15 per 1000) and 1 out of 862 (rate 1.16 per 1000) respectively. It was noted that prevalence of HIV infection in the hospital attending population with unspecified risk factor (medical, surgical and antenatal clinics) was not a matter of serious concern. The importance of finding out risk factors in females attending antenatal clinic is evident from the study.

Coxsackie B virus in the etiology of heart diseases in Delhi

Coxsackie B group of viruses have been long considered as the precipitating factor in heart diseases. Their association with various heart diseases especially pericarditis, myocarditis and myopericarditis is known, but now their association is also known with cardiomyopathy and ischaemic heart diseases. A study was carried out on 87 patients suffering from various heart diseases and the role of Coxackie B virus infection was studied. The study included 25 control subjects. Thirty patients (34.5%) were found to be having high antibody titre for at least one of coxsackie B virus group with coxsackie B3 and B4 being the two commonest types. Serum IgM immunoglobulins were raised in acute infective disorders like pericarditis, myocarditis and myopericarditis but IgG, IgA and IgM levels were normal in ischaemic heart diseases and cardiomyopathy.

Diagnostic utility of the estimation of mycobacterial Antigen A60 specific immunoglobulins IgM, IgA and IgG in the sera of cases of adult human tuberculosis

SETTING

An ELISA assay based on mycobacterial Antigen A60 for the estimation of Mycobacterium-specific immunoglobulins in the serum has been used successfully for the rapid diagnosis of tuberculosis in studies done in the Western countries. There are hardly any similar large scale studies in India.

OBJECTIVE

To evaluate the utility of this ELISA test for rapid diagnosis of different clinical forms of tuberculosis in an adult Indian population.

DESIGN

ELISA test based on mycobacterial antigen A60 (Anda Biologicals, France) was used to estimate specific IgM, IgA and IgG antibodies in the sera obtained from 337 cases of tuberculosis and 131 controls in the population of Delhi (India).

RESULTS

Of the 131 controls, only 9.9% were positive for IgM, 7.6% for IgG, 6.1% for IgA and 9.9% when an IgA and IgG combination was considered. Of 122 cases of active pulmonary tuberculosis, 41% were positive for IgM, 86.8% for IgA, 88.5% for IgG and a very high positivity (98.3%) was seen when IgA and IgG estimations were combined. A relatively low seropositivity was observed in 25 cases of pleural tuberculosis. The corresponding figures in 130 cases of extrapulmonary tuberculosis were 22.3%, 68.4%, 73.8% and 86.15%. When 60 cases of pulmonary tuberculosis who had been successfully treated with antituberculosis drugs were analyzed the rates of seropositivity fell to 11.6%, 46.6%, 58.3% and 66.6% respectively.

CONCLUSION

Our findings point to a very good sensitivity (91.6%) and specificity (90.0%) of the test when combined IgA and IgG antibody titres are considered, to detect cases of adult tuberculosis. The role of IgM estimation can be restricted to the detection of cases of reactivation of tuberculosis.

Pregnancy induced hypertension: changes in coagulation profile of newborns

Coagulation parameters and platelet count were studied in 30 neonates of mothers with pregnancy induced hypertension (PIH). 30 neonates born to normotensive mothers were taken as controls. The test group was further subdivided as neonates born to mothers with gestational hypertension, pre-eclamptic toxemia and eclampsia. The values of Prothrombin Time, Partial Thromboplastin Time with Kaolin, Thrombin Time, Fibrinogen Degradation Products were significantly raised and Fibrinogen and Platelet count were reduced significantly in both term and preterm test groups as compared to controls. The derangement in coagulation parameters was more marked with increasing severity of PIH.

A bacteriological study in hospitalized children with pneumonia

A total of 110 consecutive hospitalized children with severe lower respirator tract infection were studied with the aim of determining the main bacterial pathogens responsible. Of these, 57 were classified as severe pneumonia and 53 as very severe pneumonia. Streptococcus pneumoniae was the most common organism identified in 24.6% and 32.1% of cases of severe and very severe pneumonia, respectively, followed by Haemophilus influenzae type b, which was seen in 17.5% and 20.8%, respectively. The highest diagnostic yield was with the latex particle agglutination test on serum and urine. Blood culture was positive in only ten of the 110 children. No difference was found between the aetiological agents identified in severe and very severe cases of pneumonia. Therefore, the use of different parenteral antibiotics for two clinically defined groups of pneumonia, as recommended by WHO in their standard case management guidelines for the ARI control programme, does not seem necessary.

Widespread emergence of Vibrio cholerae 0139 in India

The National Institute of Communicable Diseases (NICD) has been monitoring the incidence of laboratory confirmed cases of cholera in Delhi in collaboration with Infectious Diseases Hospital (IDH) since 1965. Cholera and cholera-like cases from all hospitals in Delhi are admitted in IDH and the rectal swabs of all such cases are processed for isolation of Vibrio cholerae at NICD laboratory. Since April 1993, there has been isolation of Vibrio cholerae serotype 0139, in increasing numbers (831 out of 2,830, 29.2%) The isolates have been characterized and enterotoxin studies carried out. As a referral laboratory NICD has also confirmed the causative role of Vibrio cholerae 0139 in diarrhea outbreaks from various parts of the country. The implications of establishment of this newer serotype of Vibrio cholerae, as a potential epidemic strain are discussed.

Cloning, characterization, and functional expression of acs, the gene which encodes acetyl coenzyme A synthetase in Escherichia coli

Acetyl coenzyme A synthetase (Acs) activates acetate to acetyl coenzyme A through an acetyladenylate intermediate; two other enzymes, acetate kinase (Ack) and phosphotransacetylase (Pta), activate acetate through an acetyl phosphate intermediate. We subcloned acs, the Escherichia coli open reading frame purported to encode Acs (F. R. Blattner, V. Burland, G. Plunkett III, H. J. Sofia, and D. L. Daniels, Nucleic Acids Res. 21:5408-5417, 1993). We constructed a mutant allele, delta acs::Km, with the central 0.72-kb BclI-BclI portion of acs deleted, and recombined it into the chromosome. Whereas wild-type cells grew well on acetate across a wide range of concentrations (2.5 to 50 mM), those deleted for acs grew poorly on low concentrations (< or = 10 mM), those deleted for ackA and pta (which encode Ack and Pta, respectively) grew poorly on high concentrations (> or = 25 mM), and those deleted for acs, ackA, and pta did not grow on acetate at any concentration tested. Expression of acs from a multicopy plasmid restored growth to cells deleted for all three genes. Relative to wild-type cells, those deleted for acs did not activate acetate as well, those deleted for ackA and pta displayed even less activity, and those deleted for all three genes did not activate acetate at any concentration tested. Induction of acs resulted in expression of a 72-kDa protein, as predicted by the reported sequence. This protein immunoreacted with antiserum raised against purified Acs isolated from an unrelated species, Methanothrix soehngenii. The purified E. coli Acs then was used to raise anti-E. coli Acs antiserum, which immunoreacted with a 72-kDa protein expressed by wild-type cells but not by those deleted for acs. When purified in the presence, but not in the absence, of coenzyme A, the E. coli enzyme activated acetate across a wide range of concentrations in a coenzyme A-dependent manner. On the basis of these and other observations, we conclude that this open reading frame encodes the acetate-activating enzyme, Acs.