Chlamydia trachomatis antigen detection in pregnancy and its verification by antibody blocking assay.

PURPOSE: To detect the prevalence of genital infection caused by Chlamydia trachomatis in pregnant women and also to confirm the positive results using blocking antibody assay. METHODS: Endocervical specimens were collected from 200 symptomatic and asymptomatic pregnant women attending the ANC OPD at M P Shah Medical College, Jamnagar. The samples were tested for presence of Chlamydia trachomatis antigen using the monoclonal antibody. Blocking antibody assay was used to further verify the positive results. RESULTS: Out of 200 pregnant women, 38 (19%) were found positive for Chlamydia trachomatis antigen. Out of the 68 symptomatic patients, C. trachomatis antigen was detected in 26.4%. After verification of the positive samples 13.6% of the asymptomatic pregnant women were found to be harbouring the infection in their genital tract. Two (5.2%) out of the 38 positive samples, on verification with the blocking antibody assay, were found to be false positive by IDEIA,TM thus the specificity of the IDEIATM being 94.8%. In patients with previous history of abortions, 27.7% were tested positive for C. trachomatis infection. CONCLUSIONS: Significant number of pregnant women shad C. trachomatis antigen in their endocervical canal, which can be easily diagnosed by this simple enzyme immuno assay having a specificity of 94.8%. Verification of positive results by antibody blocking assay can further improve the specificity of this non-culture test. Asymptomatic patients should also be screened for the infection. History of previous abortions places the patient at a higher risk for C. trachomatis infection thus such patients should be definitely tested for chlamydia infection.

Methicillin resistant Staphylococcus aureus (MRSA): the associated risk factors.

Methicillin Resistant Staphylococcus Aureus (MRSA) infections are common among hospitalized patients in whom surgical/medical therapy provides easy and ample opportunity for infection. The present study was conducted to examine the incidence of MRSA amongst patients from burns and orthopaedic units which are high risk units, and to see the correlation of the risk factors associated with these infections. Four hundred and fifty patients from the above two units were included with complete clinical details. Pus samples/swabs were transported in glucose broth and subsequent identification of MRSA was based on standard techniques. The incidence of MRSA infection was found to be 17.5% while the nasal carriage of this pathogen was seen in 2.9% patients. The risk factors which were found to be significantly associated with these infections were prolonged hospital stay, (16.95+6.7d) previous history of hospitalization during the last three months (38%), intake of broad spectrum antibiotics within the last two weeks (39.2%), prior history of intake of any intravenous drug (6.3%) and carriage of Staphylococcus aureus (30.3%) particularly MRSA (61.5%) in nose. Since these risk factors were found to be significant, it is therefore essential to control and prevent these factors to minimize the spread of these multi drug resistant MRSA infections.

Bacteriophage therapy: an alternative to conventional antibiotics.

Bacteriophage therapy is an important alternative to antibiotics in the current era of multidrug resistant pathogens. We reviewed the studies that dealt with the therapeutic use of phages from 1966-1996 and few latest ongoing phage therapy projects via internet. Phages were used topically, orally or systemically in Polish and Soviet studies. The success rate found in these studies was 80-95% with few gastrointeslinal or allergic side effects. British studies also demonstrated significant efficacy of phages against Escherichia coli, Acinetobacter spp., Pseudomonas spp and Staphylococcus aureus. US studies dealt with improving the bioavailability of phage. Problems faced in these studies have also been discussed. In conclusion, phage therapy may prove as an important alternative to antibiotics for treating multidrug resistant pathogens.

Rising quinolone resistance in Neisseria gonorrhoeae isolates from New Delhi.

BACKGROUND & OBJECTIVES: Treatment for gonorrhoea with fluoroquinolones is recommended. However, reduced susceptibility and treatment failure with fluoroquinolones has recently been reported. We undertook to study the antibiotic susceptibility pattern and the incidence of quinolone resistance in 36 consecutive isolates of Neisseria gonorrhoeae from April to November 2000. METHOD: Antibiotic susceptibility testing was performed by the Kirby Bauer disc diffusion technique and minimum inhibitory concentration (MIC) of ciprofloxacin was determined by the agar dilution method. Penicillinase producing N. gonorrhoeae (PPNG) were identified by using the nitrocefin disc method. RESULTS: Thirty six strains of N. gonorrhoeae obtained from 44 consecutive male patients (81.9%) were studied. By the disc diffusion method, only 3 (8.3%) of these isolates were found to be sensitive to ciprofloxacin. All isolates were sensitive to ceftriaxone while 23 (63.9%) were sensitive to tetracycline and 12 (33.3%) to penicillin. Four (11.1%) of the N. gonorrhoeae isolates were PPNG. Twenty seven (75%) isolates were found to be resistant to ciprofloxacin by MIC determination. INTERPRETATION & CONCLUSION: Incidence of ciprofloxacin resistance amongst N. gonorrhoeae isolates is on the rise in New Delhi. Periodic monitoring of antimicrobial susceptibility pattern of N. gonorrhoeae to antimicrobials other than quinolones is essential to prevent treatment failure in patients with gonorrhoea.

A study on Staphylococcus aureus strains submitted to a reference laboratory.

BACKGROUND & OBJECTIVES: Staphylococcus aureus is regarded as one of the most devastating human pathogens. Recently there have been reports of increasing incidence of S. aureus strains resistant to methicillin (MRSA). A surveillance study was undertaken to record the occurrence of MRSA and to study the prevalence of various phage groups in India. METHODS: A total of 7574 strains of S. aureus received during 1992-98 at the National Staphylococcal Phage Typing Centre, New Delhi were tested for methicillin resistance and susceptibility to phages of the International basic set. The occurrence of various phage groups between MRSA and MSSA (methicillin sensitive S. aureus) was compared. Results were analyzed according to the geographical origin and source of isolation of the strains. RESULTS: The dominant phage group from different parts of the country was phage group III. Prevalence of phage group III among the MRSA and MSSA isolates was 62.32 and 33.95 per cent respectively. The highest isolation of phage group III strains was from nasal carriers (45.94%), phage group II strains from skin (8.74%), phage group I strains from blood (19.44%) and nontypable strains from the environment (80.68%). An increase in the occurrence of MRSA has been noticed from 9.83 per cent in 1992 to 45.44 per cent in 1998. INTERPRETATION & CONCLUSION: S. aureus strains of phage group III are prevalent in India. The increase in occurrence of MRSA indicates an alarming spread of these organisms. A constant monitoring is important to take appropriate and timely measures to control their spread.

Study of methicillin resistant S. aureus (MRSA) isolates from high risk patients.

MRSA is an important hospital pathogen, the incidence of which is increasing every year especially in high risk groups. The present study was performed in high risk patients admitted in burns and orthopaedic units of LN hospital to study the infection rate of MRSA from these units. The proportion of MRSA amongst S. aureus isolates was found to be 51.6% and these isolates were multidrug resistant. Phage typing of these isolates gave a typeability of 41.8% using the MRSA set of phages. Biotyping of these isolates could divide them into four groups. The study shows a high incidence of MRSA from burns and orthopaedic units with a high level of antibiotic resistance amongst these isolates.

Candidemia in neonatal intensive care unit.

The present study was conducted over a period of 6 months to determine the Candida species causing candidemia in a neonatal intensive care unit and to analyse the risk factors associated with acquisition of significant fungemia. Speciation of the 19 isolated Candida spp was done by the standard techniques. Antimicrobial susceptibility of these isolates was determined by disc diffusion method against Amphotericin B, Fluconazole, Ketoconozole and 5-Flucytosine. Candida glabrata was the most common species involved (42.1%). Other species isolated were C. tropicalis (31.6%). Calbicans (21.1%) and C.parapsilosis (5.2%). All the isolates were sensitive to Amphotericin B. Resistance to other antigungal agents was seen only in C. globrata. Significant candidemia was seen in 14/19 (72.6%) of neonates. Risk factors found to be associated with significant candidemis in these neonates included intake of multiple broad-spectrum antibiotics (p<0.0001), use of total parenteral nutrition (p<0.045) and ventilators (p<0.0001).

Filariasis as a cause of pleural effusion.

Filariasis, a mosquito borne disease is endemic in many tropical countries and sub tropics including India. A 44 years old male presented with signs and symptoms of pleural effusion. Pleural fluid on examination was exdudative in nature and showed presence of microfilariae of Wuchereria bancrofti.

Identification of yeasts from clinical specimens by oxidase test.

A total of 100 yeasts and yeast like fungi isolates from clinical specimens were negative for oxidase production on Sabouraud dextrose agar. When grown on Columbia agar, chocolate agar, tryptose agar, Mueller-Hinton agar, brain heart infusion and a medium resembling Sabouraud's dextrose agar but with starch instead of dextrose, all the isolate of Candida albicans (55), C. guilliermondii (6), C. parapsilosis (14), C. tropicalis (6), C. pseudotropicalis (6) and Crytococcus neoformans (2) were positive for oxidase producation. Torulopsis glabrata (2), Saccharomyces cervisiae (2) and two out of seven isolates of C. krusei were negative for oxidase test.

Characterization of methicillin resistant Staphylococcus aureus strains by a set of MRSA phages.

A recently developed international set of phages for typing methicillin resistant Staphylococcus aureus (MRSA) was used to characterize 300 strains of MRSA. The results were compared to that of phage typing with conventional phages and reverse phage typing. The use of MRSA phages increased the percentage typability from 17.6 per cent with the conventional set to 45.6 per cent with MRSA set and the strains were recognised as five distinct phage pattern viz., 622, M3/M5, MR8/MR12/MR25, 30/33/38 and mixed group. Phage type 622 was the most prevalent. On reverse phage typing 73 per cent strains could be typed with most strains belonging to one pattern i.e., 83A complex with limited discrimination. These 83A strains were highly resistant to erythromycin (98%) and tetracycline (93%). Our results show that MRSA phages are more useful in increasing typability and discrimination between the strains as compared to the conventional phages, reverse phage typing, and antibiogramtyping.

Community acquired methicillin resistant Staphylococcsus aureus: a new threat for hospital outbreaks?

Methicillin resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen. Recently, there have been reports of increasing prevalence of MRSA in the community. We here report an outbreak of post operative wound sepsis by MRSA in the surgical ward of LN hospital. A surveillance study for MRSA was undertaken in the corresponding surgical ward, operation theater and OPD and the source of this outbreak was traced to an outdoor patient with community acquired MRSA infection. A total of 320 clinical and environmental samples were screened for MRSA. Seventy (21.8%) S. aureus were obtained, of which 12.8% were resistant to methicillin. 14% of the MRSA infections were from the community. Nasal carriage rates of MRSA in the screened hospital staff and admitted patients were 5.8% and 4.3% respectively. None of the environmental sites sampled yielded MRSA. A study of antibiogram revealed that all the MRSA were uniformly resistant to penicillin, erythromycin, gentamicin, tobramycin and tetracycline and sensitive to vancomycin. All isolates belonged to the same biotype and were nontypable by the standard set of phages.

Evaluation of serological status of rubella & mumps in children below five years.

A cross-sectional study was carried out on 321 serum samples to detect rubella and mumps antibodies in children below five years and to assess the optimum age for immunization against rubella and mumps. Seropositivity to rubella was 33.3 per cent in children below nine months, 16.9 per cent at 9-12 months and 25.5 per cent by two years. Mean antibody levels for rubella were low at nine months to one year and remained so till five years of age. Similarly, seropositivity for mumps was 53.3 per cent below nine months, 20.3 per cent at 9-12 months and 40 per cent by two years. Mean antibody levels for mumps were low between nine months to two years with a slight rise by five years. The findings suggest that a large majority of children are at risk by the age of nine months in our population and the measles, mumps and rubella (MMR) vaccination at this age may be most beneficial.

Screening for TORCH infections in pregnant women: a report from Delhi.

Primary TORCH infections (toxoplasmosis, rubella, cytomegalovirus and herpes simplex virus type 1 and 2) in the mother can lead to severe fetal anomalies or even fetal loss. A prospective study was designed to detect the seroprevalence of IgM antibodies to Toxoplasma gondii, rubella virus and cytomegalovirus and IgG antibodies to herpes simplex virus type 1 and 2. One hundred and twenty pregnant women presenting to the antenatal clinic of a tertiary health center were included in this study. Out of these 120 women 112 (93.4%) had evidence of one or more infections. Prevalence of IgG antibodies to HSV was 70%. Seropositivities for toxoplasmosis, rubella and CMV respectively were 11.6, 8.3 and 20.8%. Our data demonstrating high frequency of primary infections during pregnancy support the conclusion that routine prenatal TORCH screening is justified.

Diagnostic utility of ELISA test using antigen A60 in suspected cases of tuberculous meningitis in paediatric age group.

The aim of the study was evaluation of the utility of ELISA test using antigen A60 for rapid diagnosis of tuberculous menigitis (TBM) in paediatric age group. ELISA test based on mycrobacterial antigen A60 (Anda biological, France) was used to estimate specific IgM and IgG antibodies in the sera and CSF of 20 suspected cases of TBM which were selected on the basis of numerous parameters and were smear negative on concentrated smear of CSF. Sera of 20 Montoux negative healthy children was taken as control by detecting IgM and IgG antibodies to A60 antigen. Response to anti-tubercular treatment was observed in all the suspected cases of TBM. This study showed that specificity for diagnosis of TBM by detecting IgM and IgG antibodies in sera was 90% and 80% respectively. Sensitivity of the test by detecting IgM and IgG antibodies in sera was 85% and 80% respectively with positive predictive value of 89.47% for IgM antibody and 80% for IgG antibody. In CSF IgM and IgG antibodies were found in 75% and 60% cases respectively. Both were positive only in 60% of cases. It is concluded from this study that 80-85% cases of TBM in paediatric age group have eigher IgM or IgG antibodies in sera whereas 60-75% have antibodies in CSF.

Association of hepatitis C virus & hepatitis B virus in chronic liver disease.

Hepatitis C virus (HCV) as a cause of chronic liver disease (CLD) was assessed by testing anti-HCV antibodies in the serum samples of 55 patients of chronic hepatitis (17), cirrhosis (32) and hepatocellular carcinoma (6). All the samples were also tested for the presence of HCV RNA by reverse transcription polymerase chain reaction (RT-PCR) using primers from the 5' non-coding region (NCR) and the relationship between the serological parameters and presence of HCV RNA was studied. The association of hepatitis B virus (HBV) with HCV in this group was evaluated by testing for the anti HBc antibodies (IgG and IgM separately) and HBsAg. The biochemical parameters and involvement of other risk factors were also studied. Twenty two (40%) patients were found to be HCV positive and 17 (77.3%) of these had evidence of infection or past exposure to HBV. On comparing the sensitivities of ELISA with that of PCR for the detection of HCV, we observed no significant difference between the two methods (P > 0.05, McNemar's test). Eighteen patients had no evidence of HBV or HCV infection. Our results indicate that HCV is next only to HBV in the causation of CLD. It is suggested that RT-PCR be used with antibody detection by ELISA for reliable detection of HCV infection.

The 1996 outbreak of dengue hemorrhagic fever in Delhi, India.

A major outbreak of dengue hemorrhagic fever (DHF) affected more than 10,000 people in Delhi and neighboring areas in 1996. The outbreak started in September, peaked in October to November and lasted till early December. The clinical and laboratory data of 515 adult patients admitted to Lok Nayak Hospital, New Delhi were reviewed. Fever (100%), myalgias and malaise (96%), abdominal pain (10.2%) and vomiting (8.7%) were the prominent presenting features. Hemorrhagic manifestations were seen in all patients- a positive tourniquet test (21.2%), scattered petechial rash (23.07%), confluent rash (2.7%), epistaxis (38.4%), gum bleeds (28.06%) and hematemesis (22.86%) being the major bleeding manifestations. Hepatomegaly was observed in 96% of the patients. Laboratory investigations revealed thrombocytopenia, hemoconcentration and leukopenia. Serological confirmation with a microcapture ELISA technic was done in 143/515 patients. The mortality rate was 6.6% and, multiple bleeding manifestations, severe thrombocytopenia, hypoproteinemia and dengue shock syndrome (DSS) were associated with a higher mortality.

Sensitivity to the bactericidal effect of human serum of Proteus strains from clinical specimens.

A total of 257 Proteus strains isolated from urinary tract infection, blood, wound and faeces were studied. Of the strains tested 31 (12 percent) were serum sensitive, 182 (71 percent) were serum resistant and the remaining 44 (17 percent) showed intermediate sensitivity to the pooled normal human serum (PNHS). Strains isolated from adult urines and blood cultures were significantly more sensitive than strains of faecal origin (p < 0.01). No significant difference was seen between strains from faeces and wounds.

Serum beta 2-microglobulin as a tumour marker in space occupying lesions of central nervous system.

We prospectively evaluated serum concentrations of beta 2-microglobulin in twenty healthy controls and fifty cases of CT scan proven and operated intracranial tumours. The later group comprised of twenty subjects of benign and thirty cases of malignant tumours respectively. Mean serum beta 2-microglobulin in healthy subjects was 1.80 +/- 0.5 mg/ litre, none had value of more than 3.0 mg/ltr. On the contrary 75% of benign and 63.3% of malignant tumour cases had statistically significant rise in the beta 2-microglobulin. Elevated serum level of beta 2-microglobulin may prove to be a reliable tumour marker.