Occurrence and detection of AmpC beta lactamases among clinical isolates of E. coli and K. pneumoniae causing UTI.

Presence of Bush class C enzymes in uropathogenic strains of Klebsiella pneumoniae & E. coli resistant to extended spectrum cephalosporins is an emerging threat to clinical therapeutics. These resistant strains result in considerable treatment failure and cannot be detected by routine antibiotic sensitivity screening methods. An effort was therefore made to study AmpC beta lactamase production in E. coli and Klebsiella pneumoniae strains causing UTI. A total of 126 E. coli and 49 K. pneumnoniae strains isolated from urine samples were selected for study out of which AmpC beta lactamase production was seen in 23% E. coli (29 isolates) and 18% K. pneumoniae (49 isolates). The susceptibility of AmpC beta lactamase producers to Imipenem, Nitrofurantoin and Amikacin was found to be 100%, 92% and 80% respectively. Thereby the present study emphasizes the importance of monitoring and control of usage of extended spectrum cephalosporins.

Prevalence of extended spectrum beta-lactamases producing clinical isolates from patients of urinary tract infection in a tertiary care hospital in Delhi.

A total of 250 urinary isolates (188 Escherichia coli and 62 Klebsiella pneumoniae) were studied for ESBL production by double disc approximation test and disc diffusion confirmatory test (NCCLS). ESBL production was found to be 56% in E. coli and 52% in K. pneumoniae. The double disc approximation test showed false ESBL production in five (2.6%) isolates of E. coli and one (1.6%) K. pneumoniae. The susceptibility of ESBL producers to imipenem, amikacin, nitrofurantion was found to be 100%, 86% and 84% respectively. A high degree of co-resistance to co- trimaxazole and norfloxacin was found in strains of ESBL producers. Seventy five per cent of ESBL producers detected were from hospitalized patients admitted in ICU or undergoing surgery.

Isospora belli infection in a malnourished child.

Isospora belli, a coccidian parasite usually causes a self limiting illness of acute onset with fever, diarrhoea and colicky pain in a normal host. In immunocompromised patients human isosporiasis becomes chronic. We report a case of a malnourished 9 year old female child who presented with complaints of loose stools, nausea, vomiting and weight loss for the past three months. Stool examination revealed immature oocysts of Isospora belli. The patient was successfully treated with TMP-SMX.

Chlamydia trachomatis and human papillomavirus infection in Indian women with sexually transmitted diseases and cervical precancerous and cancerous lesions.

OBJECTIVES: Sexually transmitted diseases (STDs) and anogenital cancers are the major health problems in Indian women but no reliable estimate of the prevalence of either genital chlamydial infection or human papillomavirus (HPV) infection in STD patients is available. The aim of this study was to detect the frequency of Chlamydia trachomatis and the most prevalent high-risk HPV type 16 (HPV 16) infection in Indian women, with STDs and precancerous and cancerous lesions of the uterine cervix by polymerase chain reaction (PCR), and their comparison with those of conventional serology and antigen tests used for C. trachomatis detection. METHODS: Endocervical swabs or scrapes were collected from 50 women with STDs and 30 normal healthy women attending the STD clinics of Smt. Sucheta Kripalani Hospital, New Delhi. Scraped cervical cell specimens were also collected from 50 women with precancerous and cancerous lesions of the uterine cervix. Detection of C. trachomatis and HPV was carried out by PCR using chlamydia and HPV genome-specific oligonucleotide primers. The detection of chlamydial antigen and IgG-specific antibodies was carried out by enzyme immunoassay (EIA) and serological enzyme-linked immunosorbent assay (ELISA), respectively. RESULTS: A chlamydia plasmid-based PCR assay detected 50% (25 of 50) positivity of C. trachomatis in STD patients and HPV 16 DNA was found in 30% (15 of 50) of these cases which are significantly higher than those found in healthy controls. The PCR estimate of chlamydia was found to be higher than its reported frequency by tissue culture. The EIA could detect chlamydial antigen in only 13 cases (26%) while serological ELISA revealed evidence of chlamydia IgG-specific antibodies in 26 (52%) cases. Interestingly, in women with precancerous and cancerous lesions, the rate of HPV 16 infection was very high (52% and 72%, respectively), whereas the frequency of chlamydia infection was found to be 12-22% only. Occurrence of other sexually transmitted agents was also evaluated in the women. CONCLUSIONS: This is the first PCR estimate of genital chlamydial (50%) and HPV 16 (30%) infection in STD patients and women with precancerous and cancerous lesions of the uterine cervix in India. The PCR method seems to be a good alternative to tissue culture.

Neisseria meningitidis: serotyping and subtyping by whole cell ELISA.

Twenty strains of Neisseria meningitidis isolated from clinically diagnosed cases of meningococcal disease were subjected to serogrouping, employing slide agglutination followed by serotyping and serosubtyping by whole cell ELISA using monoclonal typing antisera. All isolates were from sporadic cases of meningitis during a period of two years from various hospitals in Delhi. All 20 isolates were grouped as serogroup A and typed as serotype 4, except one strain which was untypable. On serosubtyping the isolates were found to belong to P1.9 (7 strains) followed by P1.1 (5), P1.9 (2), P1.16,1 (2), P1.6,10 (2), P1.10,7,1 (1) and non-subtypable (1).

Helicobacter pylori infection in recurrent abdominal pain.

OBJECTIVE: To study the relationship between Helicobacter pylori (Hp) infection and recurrent abdominal pain (RAP) and to evaluate various modalities to diagnose Hp infection. DESIGN: Prospective case control study. SETTING: Teaching hospital. METHODS: Children between 3-12 years of age with RAP in whom upper gastrointestinal endoscopic examination was indicated were studied. Endoscopic biopsy specimen were collected from duodenum, antrum and esophagus. Apart from histopathological examination of biopsy material, rapid urease test (RUT) of the antral biopsy specimen and blood examination to estimate specific IgG antibodies to Hp by Indirect Solid Phase Enzyme Immunoassay was performed. The results of Hp IgG antibodies was compared with age matched controls. RESULTS: Thirty one children with RAP were subjected to endoscopic examination and their anti Hp IgG antibodies status compared with 26 controls. Hp colonization was detected in 7 children (23%) with RAP; by RUT in 23% and antral biopsy in 16% of cases. Anti Hp IgG antibodies were also positive in almost equal proportion (19%) of controls (p = 0.757). Endoscopic examination revealed esophagitis in 16% of cases and none had evidence of gastric or duodenal erosion, ulcer or cobblestone appearance of antrum. A significant correlation of Hp was noticed with chronic antral gastritis (p = 0.002), chronic duodenitis (p = 0.02) and age > 10 years (p = 0.02). No significant correlation was noticed between Hp colonization and various socioeconomic risk factors. CONCLUSION: Hp does not seem to be commonly associated with RAP in our patient population as Hp colonization was detected in only 23% of cases which was not significantly higher than the seroprevalence of anti Hp IgG antibodies in the controls. However, a small sample size of our study limits drawing any firm conclusions. Antral gastritis and chronic duodenitis had a significant correlation with Hp colonization. RUT was found to be a reliable diagnostic test to detect Hp.

HTLV-I in HIV seropositive Indian blood donors.

One hundred HIV seropositive blood donors were screened for the presence of antibodies to HTLV-I by passive agglutination test from 1994 to 1996. Thirty two percent of the HIV-I seropositive blood donors were found to be positive for HTLV-I (Titre 1:16). Only Six percent of the HIV-seronegative donors were found to be positive for HTLV-I indicating thereby that it should be mandatory to screen all the blood samples for transfusion for HTLV-I antibodies also.

Comparison of enzyme linked immunosorbent assay and indirect haemagglutination test in serologic diagnosis of toxoplasmosis.

The antibody response against Toxoplasma gondii was evaluated by ELISA and indirect haemagglutination test (IHA) in 100 antenatal cases with bad obstetric history. 30 per cent of the cases were found to be positive by the IgM ELISA test and 22 per cent were positive by the IHA test. ELISA was found to be a more specific, reliable and easy test for screening of antenatal cases.

Screening for chlamydial infections in women with pelvic inflammatory diseases.

One hundred female patients clinically diagnosed as pelvic inflammatory disease (PID) were studied for the presence of chlamydial infection by cytology and antigen detection. Cervical smears stained by Giemsa revealed inclusion bodies, only in 3 percent of cases. While using Immunocomb Enzyme Immunoassay (EIA) test, antigen was detected in 13% of cases, thereby showing that antigen detection is a better method than cell cytology. A significant correlation with the low socioeconomic status and younger age group was seen in patients showing presence of Chlamydia trachomatis antigen.

Giardiasis--clinical and diagnostic perspective.

Fifty patients of chronic diarrhoea in the pediatric age group admitted in Kalawati Saran Children's Hospital were studied. Thirty cases were diagnosed to be suffering from giardiasis based on microscopy of fecal and/or duodenal fluid specimens. Fecal specimen microscopy missed two cases which were diagnosed by duodenal aspirate microscopy and vice-versa. All fecal specimens were negative on culture, while duodenal aspirate culture gave large number of false negative results. Serum immunoglobulin levels did not show significant changes. Thus, routine microscopic testing is presently the best means for early diagnosis of giardiasis.

Screening for Chlamydial infection in women attending STD clinic by polymerase chain reaction, ELISA and cell cytology.

Thirty five female patients with endocervicitis attending STD clinic were studied for the presence of Chlamydial infection by Polymerase Chain Reaction (PCR), Enzyme Immunoassay (EIA) and Cell Cytology. PCR was found to be positive in 54.2% of patients, Enzyme-Linked Immunosorbent Assay (ELISA) in 25.7% of patients, but cell cytology revealed the presence of inclusion bodies only in 3% of the cases, thereby showing that polymerase chain reaction is a better method for detection of Chlamydia trachomatis than EIA and cell cytology.

Study of diagnostic modalities and pathology of Helicobacter pylori infection in children.

To evaluate various diagnostic tests for Helicobacter pylori (Hp) in children, and to study the spectrum of endoscopic and histological changes in the stomach and duodenum of children with gastroduodenal disorders, associated with Hp infection Children below 12 years of age with various gastroduodenal disorders requiring upper gastrointestinal endoscopy were studied. Endoscopic biopsy specimens were collected from duodenum and antrum. Apart from histopathological examination of biopsy material, rapid urease test (RUT) of the antral biopsy specimen and blood examination to estimate specific IgG antibodies to Hp by Indirect Solid Phase Enzyme Immunoassay was performed. Forty seven children were included. Nine (19.1%) of them were positive both by serology and RUT. Seven (14.9%) were positive by histology. A significant correlation of Hp was noticed with chronic antral gastritis (p = 0.002) and chronic duodenitis (p = 0.006). Age equal to or more than 10 years was found to be significant risk factor for acquiring Hp infection. Prevalence of Hp in children with gastroduodenal complaints was found to be 19%. Both RUT and serology were found to be reliable diagnostic tests for Hp as compared with histology. Antral gastritis and chronic duodenitis had a significant correlation with Hp colonization.