Association Between Neuropsychiatric Morbidity and Streptococcal Infections in Children.

We conducted a case control study to study the association between neuropsychiatric morbidity and group A streptococcal infections in children. Twenty two cases of neuropsychiatric morbidity were compared with 64 controls. Fourteen (63.6%) of the 22 cases were positive for ASO and/or ADNB while 21 of the 64 controls (32.8%) were positive for either or both antibodies (OR = 3.428; CI: 1.15 – 10.18; P=0.026). We conclude that there is a statistically significant association between neuropsychiatric morbidity and streptococcal infection in children.

Needle stick injuries in a tertiary care hospital.

BACKGROUND: Accidental needle stick injuries (NSIs) are an occupational hazard for healthcare workers (HCWs). A recent increase in NSIs in a tertiary care hospital lead to a 1-year review of the pattern of injuries, with a view to determine risk factors for injury and potential interventions for prevention. METHODS: We reviewed 1-year (July 2006-June 2007) of ongoing surveillance of NSIs. RESULTS: The 296 HCWs reporting NSIs were 84 (28.4%) nurses, 27 (9.1%) nursing interns, 45 (21.6%) cleaning staff, 64 (21.6%) doctors, 47 (15.9%) medical interns and 24 (8.1%) technicians. Among the staff who had NSIs, 147 (49.7%) had a work experience of less than 1 year (n = 230, 77.7%). In 73 (24.6%) of the NSIs, the patient source was unknown. Recapping of needles caused 25 (8.5%) and other improper disposal of the sharps resulted in 55 (18.6%) of the NSIs. Immediate post-exposure prophylaxis for HCWs who reported injuries was provided. Subsequent 6-month follow-up for human immunodeficiency virus showed zero seroconversion. CONCLUSION: Improved education, prevention and reporting strategies and emphasis on appropriate disposal are needed to increase occupational safety for HCWs.

Role of quantitative endotracheal aspirate and cultures as a surveillance and diagnostic tool for ventilator associated pneumonia: A pilot study.

Background: Accurate diagnosis and appropriate treatment of ventilator associated pneumonia (VAP) is crucial for good outcomes. Endotracheal suctioning is performed in ventilated patients as part of routine care and for tracheal toileting. Aim: We evaluated if quantitative endotracheal aspirate (ETA) was a suitable alternative to bronchoalveolar lavage (BAL) for suspected VAP. In addition we assessed if surveillance ETA guided antibiotic selection for subsequent VAP. Setting and Design: Prospective study in the surgical intensive care unit (ICU) of a tertiary hospital in India. Materials and Methods: Two hundred consecutive patients with mean (standard deviation) APACHE II score of 12.3+/-5 and requiring mechanical ventilation beyond 48 hours underwent surveillance ETA cultures. A second ETA and BAL were performed if the patient developed features of VAP. The threshold for microbiological diagnosis of VAP was taken as 10 5 colony forming units/ml (cfu/ml) for ETA and 10 4 cfu/ml for BAL. Statistical Analysis: The sensitivity and specificity of surveillance and concurrent ETA aspirate cultures were compared with BAL cultures. RESULTS: VAP was suspected clinically and corroborated radiologically in 27/177 patients (15.3%). Although microbiological support for VAP was obtained by ETA in 19 patients, bronchoscopy was possible only in 13 patients, 8 of whom had isolates at significant threshold. Of the 16 organisms isolated from BAL, 11 were of significant threshold with 9/11 (82%) BAL isolates having a similar antibiogram to a concurrent ETA. Only one BAL isolate (9%), at significant threshold, was not isolated on a concurrent ETA. On the other hand just 6/11 BAL isolates (55%) had an identical antibiogram to surveillance ETA. BAL had 3 additional isolates (27%) at significant threshold not isolated on surveillance ETA. Conclusions: Concurrent quantitative ETA could substitute BAL cultures for VAP. Surveillance ETA at 48 hours of ventilation does not appear to assist with antibiotic selection for a subsequent VAP.

Prevalence of inducible clindamycin resistance in gram positive organisms in a tertiary care centre.

Gram positive organisms are one of the leading pathogens causing skin and soft tissue infections. For these infections, clindamycin is a useful alternate drug in penicillin-allergic patients. This study was conducted to investigate the prevalence of erythromycin-induced clindamycin resistance in gram positive organisms in the southern part of the country. A total of 522 consecutive clinical isolates from blood, CSF, sputum, throat, pus, and urine were collected between November 2006 and April 2007 and tested for erythromycin resistance and inducible clindamycin resistance. There was a relatively higher incidence of inducible clindamycin resistance among the MRSA isolates. We conclude, therefore, that clindamycin is not a suitable alternative antibiotic for use in staphylococcal skin and soft tissue infections.

Pyopericardium due to group D streptococcus.

Beta-hemolytic Enterococcus faecalis was isolated from the pericardial fluid obtained from a patient with pyopericardium. The patient was immunocompetent and had mild pleural effusion. He was treated with parenteral co-amoxiclav and amikacin, had underwent pericardiectomy with repeated pericardial aspiration, and recovered completely. To our knowledge, this is the first report of pyopericardium due to E. faecalis .

One year trends in the gram-negative bacterial antibiotic susceptibility patterns in a medical intensive care unit in South India.

PURPOSE: To describe the changes in antibiotic susceptibility patterns of common intensive care unit pathogens with time from the medical intensive care unit of a tertiary care hospital. METHODS: A prospective observational study was conducted in the medical intensive care unit (MICU) of a 2100 bed tertiary care hospital in South India. All data regarding patient characteristics, disease characteristics, infective agents, identified along with their antibiotic sensitivity patterns and patient outcomes were prospectively recorded in MICU data base. Various bacterial pathogen antibiotic sensitivity patterns from August 2004 to May 2005 were prospectively documented. During this period 491 patients were admitted to the MICU. Data were analyzed using excel spreadsheets. RESULTS: Ceftazidime resistance reduced in Klebsiella spp. while cefotaxime resistance increased. In E. coli however, ceftazidime and cefotaxime resistance increased. Klebsiella resistance to cefotaxime and ceftazidime ranged from 25-50% and 14-91%, while E. coli resistance to these antibiotics ranged from 50-70% and 50 to 80% respectively. In Pseudomonas and the non-fermenting gram-negative bacteria (NFGNB) ceftazidime resistance decreased. Third generation cephalosporin resistance seemed to be reducing in the NFGNB, however, carbapenem resistance appeared to be increasing, possibly due to their increasing use. CONCLUSIONS: This study demonstrates the trend in antibiotic susceptibility pattern (AST) of common gram negative infections seen in intensive care units. It demonstrates the changes seen especially after a change in the protocol antibiotic. Changes in the AST patterns of Klebsiella, E. coli, Pseudomonas and non-fermenting gram negative bacteria were seen. The data on the changing antibiotic susceptibility trends we believe is an important pillar in our efforts at infection control especially in intensive care settings.

Microbiological diagnosis of streptococcal pharyngitis: lacunae and their implications.

Post-streptococcal sequelae, especially acute rheumatic fever/rheumatic heart disease continue to occur in significant proportions in many parts of the world. Despite several attempts with various intervention strategies, little success has been achieved in the control of acute rheumatic fever/rheumatic heart disease in India. The success of the control programmes depends upon timely primary prophylaxis with benzathine penicillin for which a microbiological confirmation of group A streptococcal pharyngitis is essential. Isolation of beta hemolytic streptococci from throat cultures and their identification as GAS in the laboratory, clinches the microbiological diagnosis while demonstration of a 'significant rise' in antibody titers such as Anti-streptolysin O and Anti-deoxyribonuclease B differentiates it from a group A streptococcal carrier state or pharyngitis of a viral etiology. Despite the easiness with which these can be achieved, many laboratories in India are not equipped to do so. Enhancing bacteriological and serological facilities in laboratories across the country will drastically improve the clinician's ability to diagnose bona fide GAS pharyngitis and help to institute penicillin prophylaxis at the appropriate time. This will go a long way in enhancing the compliance to penicillin prophylaxis which is the cornerstone of any RF/RHD control program.

Evaluation of simplified DNA extraction methods for emm typing of group A streptococci.

Simplified methods of DNA extraction for amplification and sequencing for emm typing of group A streptococci (GAS) can save valuable time and cost in resource crunch situations. To evaluate this, we compared two methods of DNA extraction directly from colonies with the standard CDC cell lysate method for emm typing of 50 GAS strains isolated from children with pharyngitis and impetigo. For this, GAS colonies were transferred into two sets of PCR tubes. One set was preheated at 94 degrees C for two minutes in the thermal cycler and cooled while the other set was frozen overnight at -20 degrees C and then thawed before adding the PCR mix. For the cell lysate method, cells were treated with mutanolysin and hyaluronidase before heating at 100 degrees C for 10 minutes and cooling immediately as recommended in the CDC method. All 50 strains could be typed by sequencing the hyper variable region of the emm gene after amplification. The quality of sequences and the emm types identified were also identical. Our study shows that the two simplified DNA extraction methods directly from colonies can conveniently be used for typing a large number of GAS strains easily in relatively short time.

Incidence of carbapenem resistant nonfermenting gram negative bacilli from patients with respiratory infections in the intensive care units.

Resistance to carbapenems is commonly seen in nonfermenting gram negative bacilli (NFGNB). We document herein the prevalence of carbapenem resistance in NFGNB isolated from patients with respiratory tract infections in the intensive care units (ICUs). A total of 460 NFGNB were isolated from 606 endotracheal aspirate specimens during January through December 2003, of which 56 (12.2%) were found to be resistant to imipenem and meropenem. Of these, 24 (42.8%) were Pseudomonas aeruginosa , 8 (14.2%) were Acinetobacter spp. and 24 (42.8%) were other NFGNB. Stringent protocols such as antibiotic policies and resistance surveillance programs are mandatory to curb these bacteria in ICU settings

Extensive deep neck space abscess due to B-Haemolytic group G Streptococci-A case report.

Beta haemolytic phenotype of group G streptococci was isolated from the pus obtained from a patient with extensive deep neck space abscess. Patient was immunocompetent and made complete recovery after surgical drainage and administration of amoxycillin with clavulanic acid, amikacin and metronidazole. To our knowledge, this is the first report of deep neck space abscess due to group G streptococci.

Detecting mycobacteraemia for diagnosing tuberculosis.

BACKGROUND & OBJECTIVES: In human immunodeficiency virus (HIV) infected persons with pulmonary tuberculosis (TB), sputum may not always show acid fast bacilli (AFB). Moreover, in most cases of suspected extrapulmonary TB (irrespective of HIV status) mycobacteria-containing material is not readily available for investigation. This study evaluated whether blood culture for Mycobacterium tuberculosis bacteraemia (mycobacteraemia) help in diagnosing TB in such cases. METHODS: A total of 93 consecutive subjects with a clinical diagnosis of tuberculosis with or without laboratory confirmation, 42 with and 38 without coexisting HIV infection, and 13 patients with HIV infection without clinical evidence of TB were enrolled. Mycobacterial blood cultures were done using lysis centrifugation technique followed by subculturing onto the modified Lowenstein-Jenson medium (LJ-1) and Selective Kirchner's medium followed by subculturing onto the modified Lowenstein-Jenson medium (LJ-2, LJ-3). RESULTS: Of the 15 (16.2%) subjects with evidence of mycobacteremia in 4 (26.7%) blood was the first/ only source of diagnosing TB. Among 80 patients with clinical diagnosis of TB whether supported by laboratory tests or not, 14 (17.5%) had mycobacteraemia. Among the 21 HIV infected patients with laboratory proven TB, 9 (43%) had mycobacteraemia. INTERPRETATION & CONCLUSION: Blood culture appears to be a useful additional test to diagnose TB in persons with HIV infection. In patients without HIV infection, but with clinical picture compatible with TB, blood culture for mycobacteraemia may occasionally help in the diagnosis. We recommend the use of the lysis centrifugation technique followed by direct smear of the sediment along with inoculation of the sediment into both modified Lowenstein-Jenson medium and the Selective Kirchner's medium with subsequent subculturing onto the modified Lowenstein-Jenson medium for mycobacterial blood culture for detecting mycobacteraemia.

Evaluation of serological tests for the diagnosis of tuberculosis.

To evaluate the use of antibody detection kits in the diagnosis of pulmonary tuberculosis in an endemic area, serum samples from cases (sputum smear positive for AFB) and controls (healthy young adults) were collected and tested using five different kits. Sensitivity, specificity and predictive values were calculated using smear positivity as gold standard. Sensitivity of tests varied from 46% to 68% and the specificity from 68% to 100%. None of the kits evaluated can be used as a single screening test for tuberculosis. However kits with good specificity may be used in conjunction with conventional methods for diagnosis.

Systemic bacterial infections in bone marrow transplant patients.

The clinical microbiology department at CMC&H, Vellore in conjunction with the haematology department carries out routine surveillance of patients admitted to the hematology department. Since 1994 in a sample population of 55 patients with various underlying clinical conditions who have had bone marrow transplant, sepsis was observed in 16 patients (29%). The predominant Gram negatives associated with sepsis were non-fermenting Gram negative bacilli and all the 5 Gram positives were coagulase negative staphylococci. These organisms were susceptible to most of the routinely used antimicrobial agents. Continued surveillance is needed to determine changing trends with respect to organisms causing systemic infections and their susceptibility to antimicrobials.

Effects of intranasal challenge with group A beta haemolytic streptococcus M type 49 in Swiss albino mice.

Mice are susceptible to natural infections with streptococci and therefore can serve as suitable animal models to study experimental streptococcal infections. In an earlier study, we had shown the development of pharyngeal colonization, antibody response and histopathological changes in the heart following intranasal (IN) challenge with a rheumatogenic serotype of group A beta haemolytic streptococcus, the M type 18. To determine if nonpharyngitis associated serotypes can also elicit similar responses, 30 Swiss albino mice were challenged intranasally with 2 x 10(7) colony forming units of a skin associated serotype of group A beta haemolytic streptococcus, the M type 49. Pharyngeal colonization varied from 64% (n = 30) in the first week to 69% (n = 16) during the fourth week after IN challenge. Eleven (36.7%) of the 30 animals studied showed antibody response to DNase B (ADNB) with peak titers varying from 150 to 1200 units. Wide variations were seen in ADNB titers in individual mice. Histopathological evidence for cardiac lesions were seen in three animals. The changes were mild and varied from mild to chronic endocardial inflammation to calcification. The study shows that Swiss albino mice are also susceptible to IN challenge with skin associated strains of GABHS and therefore can serve as useful models to study the effects of experimental infection with diverse serotypes of GABHS.

Pharyngeal colonisation, ADNB response and development of cardiac lesions in mice following intranasal inoculation with group A beta haemolytic streptococcus M type 18.

Swiss albino mice from a randomly bred colony were inoculated intranasally with 1.6, 2 or 2.4 x 10(7) colony forming units of a mid-logarithmic phase culture of group A beta haemolytic streptococcus M type 18 for 3 days, 6 days or once a week respectively for three weeks. Pharyngeal colonisation could be observed in 67 (59.8%) of 112 mice on 4th day after inoculation and 14 (38%) of the 37 mice on 21st day. Out of 27 mice tested for determination of antibodies to deoxyribonuclease B at regular intervals for 98 days, 15 (55.5%) showed responses, with maximum titers varying from 50 units to 4800 units in individual mice. Histopathological evidence for cardiac lesions were seen in five (3.03%) of the 165 animals studied. These included one case of severe endocarditis, two cases of endocarditis with valvular lesions and one case with non-specific lymphocyte infiltration in the heart. One other animal showed subendocardial oval nodular aggregates. Although the cellular nature of these lesions were not determined, this study shows that Swiss albino mice can serve as suitable animal models to study experimental streptococcal infections. However these are preliminary observations and are to be confirmed and revalidated by further controlled experiments.

An outbreak of post-streptococcal reactive arthritis.

We describe an outbreak of an illness with fever, mono-, pauci- or polyarticular arthritis, and high antideoxyribonuclease B (ADNB) titres in 11 patients. Two patients had concomitant non-purulent conjunctivitis and one had endogenous endophthalmitis. There was no clinical or echocardiographic (6 patients) evidence of carditis. Blood culture grew Group A beta haemolytic streptococci in one patient. A simultaneous synovial fluid culture in this patient and similar cultures in four more patients yielded no microorganism. Most patients recovered completely, but one developed rheumatoid factor negative spondyloarthropathy. Monoarticular arthritis in several patients, the absence of carditis, and the presence of high ADNB titres without high anti-streptolysin O titres indicate that this was not acute rheumatic fever but post-streptococcal reactive arthritis (PSRA).

Prevalence of pneumococcal serotypes in invasive diseases in southern India.

Forty two pneumococcal strains obtained in Vellore, Tamil Nadu, from 42 patients with invasive diseases, namely pneumonia, meningitis, or peritonitis were typed. Over one-third of pneumococci in children and nearly half in adults were serotype followed by serogroups/types 5, 6 and 7 which were most common in children and adults taken together. These 4 serogroups/types accounted for 11 (79%) of 14 strains in children and 20 (71%) of 28 strains in adults. The remaining 11 strains belonged to 8 serogroups/types, namely 3, 4, 10, 11, 12, 13, 19 and 20.

Changing patterns of group B streptococcal serotypes associated with human infections.

One hundred strains of group B streptococci (GBS) isolated from diverse clinical specimens of patients seen in our hospital were subjected to serotyping by an indigenously prepared coagglutination system. Serotype NT/c was the most predominant (24%), followed by Ia (23%), II/c (12%) and Ib (11%). Type Ia was the most predominant in all specimens except genital samples where NT/c was the most predominant. Comparison of the distribution of serotypes identified during 1975-78 with that of the present study showed a great increase in the prevalence of types NT/c, II/c and Ia and a dramatic decline of types III, Ia/c and Ib. Despite the inclusion of reagents for newer serotypes, IV and V two strains were nontypable indicating the prevalence of hitherto unidentified GBS serotypes in our community.

Long-term preservation of streptococci.

Strains of 12 T types of group A streptococci preserved by sand desiccation and stored at 4 degrees to 10 degrees C were regularly sub-cultured to check their viability. For this, streptococci coated onto sand particles mixed with sterile sheep blood were inoculated into Todd-Hewitt broth with added blood and incubated for 24 to 48 h. Checking for viability every six months showed that group A streptococci could be preserved by this method for 21 yr. Our study shows that sand desiccation is a convenient and cheap method for the long-term preservation of streptococci in laboratories where other methods of preservation are not feasible on a regular basis.