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S Mehtar

Publications and source records attributed to S Mehtar.

At least 19 recordsLinked to original sources
PubMed2004

Unexplained HIV-1 infection in children--documenting cases and assessing for possible risk factors.

BACKGROUND: In the year 2000 we reported possible horizontal transmission of HIV-1 infection between two siblings. An investigation of three families, each with an HIV-infected child but seronegative parents, permitted this finding. Sexual abuse and surrogate breast-feeding were thought unlikely. The children had overlapping hospitalisation in a regional hospital. Since then several cases of unexplained HIV infection in children have been reported. A registry was established at Tygerberg Children's Hospital for collection of data on the extent of horizontal or unexplained transmission of HIV in children. STUDY DESIGN: Retrospective chart review. RESULTS: Fourteen children were identified, 12 from the Western Cape and 1 each from the Eastern Cape and KwaZulu-Natal. Thirteen (92%) had been hospitalised previously. In the Western Cape, children had been hospitalised in 8 hospitals. Ten of 13 (77%) were admitted as neonates and 9 of 13 (69%) had 2 or more admissions. Intravascular cannulation and intravenous drug administration occurred in all but 2 children before HIV diagnosis. CONCLUSION: We have confirmed HIV infection in a number of cases where the source of infection has been inadequately explained. Circumstantial evidence supports but does not prove nosocomial transmission. Further studies and identification of medical procedures conducive to the spread of HIV are urgently needed.

Age Distribution↗
PubMed1999

Minimum standards in laboratories for infection control.

Laboratory services should be available to support every infection control programme, whether in a hospital or community setting. The services will depend upon available resources and the expectation of the clinicians using the services. Equally, resources reflect the level of staff expertise, equipment and finances supporting laboratory practice. All information given to the clinical staff should be sensible, accurate, comprehensible and in keeping with the clinical needs of the healthcare setting. Internal and external quality controls should be rigorous. Not all laboratories are expected to provide an all-encompassing service and therefore primary, secondary and tertiary or referral laboratories should be established where necessary. It is essential to have clear protocols on laboratory usage, mutually agreed between the laboratory and clinical staff to be cost effective.

Guidelines as Topic↗
PubMed1998

New strategies for the use of mupirocin for the prevention of serious infection.

Nasal mupirocin has an important role to play in the prevention of Staphylococcus aureus infection by eliminating nasal carriage of this organism. Indeed, in many countries nasal mupirocin is one of the mainstays for controlling outbreaks of methicillin-resistant S. aureus. Eradication of nasal S. aureus with mupirocin has been shown to be effective in preventing postoperative infections in patients undergoing cardiothoracic surgery and in preventing exit-site infections in patients undergoing haemodialysis. It has been proposed that the use of mupirocin should be extended to other situations, such as the prevention of postoperative infections in patients undergoing implant surgery and the prevention of bacteraemias in high-risk patients. Clinical trials are needed to establish the efficacy of mupirocin in these situations. Both low-level and high-level resistance have been reported during treatment with nasal mupirocin. Low-level resistance does not represent a significant clinical problem but high-level resistance resulting from indiscriminate use may give grounds for concern. Further review of these issues is required. As with any antibiotic, mupirocin should be used judiciously, as part of an integrated programme of infection control.

Anti-Bacterial Agents↗
PubMed1997

A multi-centre study to compare meropenem and cefotaxime and metronidazole in the treatment of hospitalized patients with serious infections.

We conducted a prospective, multi-centre, open, randomized study in 11 UK hospitals to compare iv meropenem 1 g tds with the combination of iv cefotaxime 1 g tds and iv metronidazole 500 mg tds in patients with serious infections. One hundred and sixty-one patients were enrolled, of whom 131 were clinically evaluable (meropenem, n = 68; cefotaxime/metronidazole, n = 63). The most common infections were subsequent to intra-abdominal pathology (meropenem, n = 77%; cefotaxime/metronidazole, n = 75%), and were usually accompanied by septicaemia (meropenem, n = 61%; cefotaxime/metronidazole, n = 53%). The incidence of a satisfactory clinical response was similar in the two groups at the end of treatment (93% for meropenem; 92% for cefotaxime/metronidazole) and up to 8 weeks later (96% for meropenem; 93% for cefotaxime/metronidazole). Satisfactory bacteriological response (success or presumed success) was recorded at the end of therapy in 86% of meropenem and 88% of cefotaxime/metronidazole patients. Adverse events were reported in 32% of meropenem and 25% of cefotaxime/metronidazole patients, and most were mild or moderate and did not require discontinuation of therapy. Twenty-one patients (ten meropenem and 11 cefotaxime/metronidazole) died during the trial, underlining the severity of the infections being treated in this group of patients. None of the deaths was thought to be related to study therapy.

Adult↗
PubMed1996

Involvement of topoisomerase IV and DNA gyrase as ciprofloxacin targets in Streptococcus pneumoniae.

Ciprofloxacin-resistant mutants of Streptococcus pneumoniae 7785 were generated by stepwise selection at increasing drug concentrations. Sequence analysis of PCR products from the strains was used to examine the quinolone resistance-determining regions of the GyrA and GyrB proteins of DNA gyrase and the analogous regions of the ParC and ParE subunits of DNA topoisomerase IV. First-step mutants exhibiting low-level resistance had no detectable changes in their topoisomerase quinolone resistance-determining regions, suggesting altered permeation or another novel resistance mechanism. Nine of 10 second-step mutants exhibited an alteration in ParC at Ser-79 to Tyr or Phe or at Ala-84 to Thr. Third- and fourth-step mutants displaying high-level ciprofloxacin resistance were found to have, in addition to the ParC alteration, a change in GyrA at residues equivalent to Escherichia coli GyrA resistance hot spots Ser-83 and Asp-87 or in GyrB at Asp-435 to Asn, equivalent to E. coli Asp-426, part of a highly conserved EGDSA motif in GyrB. No ParE changes were observed. Complementary analysis of two S. pneumoniae clinical isolates displaying low-level resistance to ciprofloxacin revealed a ParC change at Ser-79 to Phe or Arg-95 to Cys but no changes in GyrA, GyrB, or ParE. A highly resistant isolate, in addition to a ParC mutation, had a GyrA alteration at the residue equivalent to E. coli Asp-87. Thus, in both laboratory strains and clinical isolates, ParC mutations preceded those in GyrA, suggesting that topoisomerase IV is a primary topoisomerase target and gyrase is a secondary target for ciprofloxacin in S. pneumoniae.

Amino Acid Sequence↗
PubMed1995

Infection control programmes--are they cost-effective?

Infection control (IC) programmes are cost-effective in the long-term but much depends on the available resources and the support from management. The funding of IC programmes at present is linked to the Microbiology Department and a separate budget needs to be established. The best use of resources is to apply a risk assessment to each situation which presents and to adapt protocols accordingly. For example, the treatment of a carrier or an infected patient with methicillin-resistant Staphylococcus aureus cost 374 pounds and 2454 pounds, respectively in 1993, the major portion of the cost being due to an increased length of stay which was two days and 10 days, respectively. It is more cost-effective to treat carriers. The other cost-effective investment is in education and reinforcement of simple messages. Formal lectures seem to be the least effective way of producing long-term effect; frequent ward visits or contacts are most effective. Also, there is better compliance when there is a perceived risk to the staff themselves. The availability of the IC team to advise helps reduce waste and therefore cost. This is particularly true of antibiotic usage where it was noted that without guidance, the antibiotic usage increased by 2000 pounds per month when compared to a similar period in the previous year. The available provisions for IC programmes in the UK are utilized exceptionally well when compared with other countries.

Anti-Bacterial Agents↗
PubMed1994

The continuing problem of 'hospital staphylococci': why?

Nosocomial infections due to staphylococci continue to pose a serious health concern worldwide. Methicillin-resistant Staphylococcus aureus (MRSA) is an important and growing cause of staphylococcal infection. The incidence of MRSA varies throughout the world, but is particularly high in Japan where the incidence is four-times that seen in Europe. The emergence of coagulase-negative staphylococci (CNS) has increased as a significant pathogen in infections associated with prosthetic implants. Evidence suggests that hand carriage by hospital staff is one way in which CNS are introduced onto catheters, intravenous lines and other implant devices. Control measures in the UK have concentrated on the reservoirs of infection, with the aim of preventing infection and the resulting morbidity, mortality and economic burden. At the North Middlesex Hospital, London, UK, an aggressive prophylactic policy for MRSA has been employed since 1987. Data show that it is six times cheaper to treat a carrier than it is to treat an infected patient. Prophylaxis therefore provides a more cost-effective way of controlling the spread of MRSA infection. Such stringent control strategies, coupled with increased awareness and adequate funding, are necessary if the spread of resistant bacteria is to be limited.

Cross Infection↗
PubMed1993

How to cost and fund an infection control programme.

Infection control (IC) services in the United Kingdom are provided as part of the microbiology services and therefore they have not, to date, been costed separately. This paper addresses the cost of providing the service, the savings that accrue from the IC policies in a hospital and, finally, the cost of infective episodes and outbreaks. The point of the exercise is to enable readers to cost their own services and separate the IC and microbiology budgets while maintaining the provision of service under one department.

Budgets↗
PubMed1992

Chloramphenicol resistance in Salmonella typhi. Report from Bombay.

Chloramphenicol resistance to Salmonella typhi in 1989 was 16% in Hinduja Hospital. From Jan to June 1990, this resistance has increased to 81%. 74 strains of blood culture isolated of S typhi obtained from Jan to June were subjected to antibiotic sensitivity testing by disc diffusion technique of Kirby and Bauer 60 strains were found to show a block resistance tochloramphenicol, Ampicillin, Co-trimoxazole, Streptomycin, Tetracycline and Carbenicillin. All strains were sensitive to quinolones. Resistance was record and MIC done in 50 resistant strains by modified National Committee for Clinical Laboratory Standards [NCCLS] according to recommended break points and resistance to Chloramphenicol was confirmed. Of the 47 strains isolated, 34 had received treatment with either chlorampheniicol, Ampicillin or Cotrimoxazole in adequate dosages. In 39 of these 47 patients, Salmonella typhi was isolated after 14 days duration of fever. Plasmid analysis revealed presence of 100 megadalton plasmid in majority of cases. Most patients responded to fluoroquinolones but amongst the admitted patients complications such as Myoglobinuria in 2 cases, perforation in 4 cases, acute Renal failure in 2 cases and typhoid spine in 1 case were seen. Phage typing results of 19 strains were E-8, 0-6.

Chloramphenicol Resistance↗
PubMed1991

The effect of disinfectants on perforated gloves.

Three types of gloves, 'Biogel', 'Regent Dispo Surgical' gloves and Ansell gammex were perforated, and contaminated with Escherichia coli or Pseudomonas aeruginosa as test organisms applied either to the hand or the glove surface. The glove surface was decontaminated with alcoholic chlorhexidine ('Hibisol'), methylated spirit, or soap and water. The experiments were performed in triplicate on three separate days. The experiments were designed to study the ability of the three disinfection methods to reduce the bacterial count of 10(6) colony forming units (cfu) ml-1 (applied to perforated gloves or hands) sufficiently to permit the re-use of such gloves for non-sterile ward procedures. The best method of disinfection was using alcoholic chlorhexidine which not only reduced glove surface carriage but also reduced transfer of bacteria to the hands through the perforation in the gloves. Soap and water was the least effective. Escherichia coli was more easily removed than P. aeruginosa. We recommend that non-sterile ward procedures may be carried out even after gloves have been perforated provided alcoholic chlorhexidine is used between each procedure to reduce cross-infection between patients.

Chlorhexidine↗
PubMed1991

Distribution and transferability of plasmids encoding trimethoprim resistance in urinary pathogens from Greece.

Of 505 strains of Enterobacteriaceae responsible for significant bacteriuria and isolated from hospital patients in two Greek cities in 1989, 151 strains (30%) were resistant to trimethoprim (MIC greater than or equal to 4 mg/L) and 220 (44%) were resistant to sulphamethoxazole (MIC greater than or equal to 64 mg/L); 127 (84%) of the trimethoprim-resistant strains exhibited high-level resistance (MIC greater than 1024 mg/L) and 121 (80%) were additionally resistant to four or more other antibiotics. Plasmids were detected in 141 (93%) of the trimethoprim-resistant strains. Trimethoprim resistance was encoded on self-transmissible plasmids in 79 (52%) of the resistant strains, and in a further seven strains (5%), plasmids coding for trimethoprim resistance could be mobilised by X+ factor. Co-transfer of various other antimicrobial resistances with trimethoprim resistance was observed, tetracycline resistance being the most common. The low degree of linkage observed between trimethoprim resistance and resistance to streptomycin and spectinomycin suggests that Tn7 is relatively uncommon in Greece. Classification of trimethoprim-resistance plasmids on the basis of their antimicrobial-resistance patterns and molecular mass revealed 39 different profiles. Overall, these findings differ from those from other European countries where the prevalence of transferable high-level trimethoprim resistance is low and where chromosomal Tn7-encoded trimethoprim resistance is common.

Bacteriuria↗
PubMed1990

A multi-centre evaluation of two chlorhexidine-containing formulations for surgical hand disinfection.

Many experimental methods have been used to assess the efficacy of products intended for surgical hand disinfection. In this study, a modification of the Peterson glove juice method was used to compare two chlorhexidine-based surgical hand disinfectants, 'Hibiscrub' and an experimental formulation, F.6115. The study was performed by four independent laboratories and data merged for analysis. There was found to be no significant difference between the two formulations. The results illustrate that this modified Peterson glove juice method has the potential to form the basis of a standard method for testing surgical hand disinfectants which is both relevant to the practical situation and reproducible in different laboratories.

Chlorhexidine↗
PubMed1990

The in-vitro activity of piperacillin/tazobactam, ciprofloxacin, ceftazidime and imipenem against multiple resistant gram-negative bacteria.

One hundred and fifty Gram-negative bacterial strains including respiratory pathogens, such as Haemophilus influenzae and Branhamella catarrhalis, and Enterobacteriaceae with known resistance to beta-lactam and other antibiotics were tested in vitro for sensitivity to piperacillin, piperacillin/tazobactam (ratio 8:1), ceftazidime, ciprofloxacin and imipenem. A 16-fold or greater reduction in the MIC90 of piperacillin was achieved by the addition of tazobactam, in the respiratory pathogens, thus bringing them within the susceptible range. Among the Enterobacteriaceae, a 32-fold or greater reduction in the MIC90 was found for Providencia stuartii, Proteus mirabilis and Aeromonas hydrophila. When compared with the other three antimicrobials, the combination was found to be active against fewer species of multiply resistant Enterobacteriaceae, but equally effective against H. influenzae and B. catarrhalis.

Anti-Bacterial Agents↗