John Philpott-Howard

Fungal infection : a common, unrecognised complication of acute liver failure

The true incidence and clinical relevance of fungal infection was ascertained in a prospective study of 50 consecutive patients with acute liver failure. Fungal infection was present in 16 (32%) patients (15 candida, one aspergillus) and in seven was considered the major cause of death. All six untreated died, while five of ten patients treated with anti-fungal therapy survived. The diagnosis was made on positive cultures from at least one significant site or on histological evidence of tissue invasion. All 16 had concomitant bacterial infection and shared features suggestive of a clinical syndrome: deterioration in coma grade after initial improvement; pyrexia unresponsive to antibiotics; established renal failure; and a markedly elevated white cell count. Fungal infection is a common, serious complication of acute liver failure and therapy is indicated for those with positive cultures. A prophylactic trial would be justified in those surviving 5 days, especially, with established renal failure.

The microbiological quality of water in dental chair units

Infection control is an important issue in the dental surgery but the potential hazards associated with contaminated dental water have received relatively little attention in recent years. The complex design of the equipment results in stagnation of water within the dental chair and subsequent amplification of contaminating environmental organisms, including pseudomonads and legionellae, to potentially hazardous levels. Immunocompromised patients may be at particular risk of infection. Very poor water quality with total bacterial counts above 10(4) ml-1 is unpleasant for all patients, and the dental chair supply should be of drinking water quality. In addition to these problems, bacteria and viruses may be aspirated from the oral cavity and contaminate the handpiece. Measures to reduce microbial contamination of dental chairs and equipment include flushing water through the chairs equipment at the beginning of each day; continuous or pulsed water chlorination, or application of biocides other than chlorine; provision of sterile bottled water in the system; and autoclaving handpieces between patients. Future dental chair design must attempt to resolve the problems associated with microbial contamination of the water supply and aerosols generated during dental procedures.

Nocardiosis in liver transplantation: variation in presentation, diagnosis and therapy.

Nocardiosis arose in seven of 191 liver transplant patients (3.7%) over a period of 3.5 years. Four patients had only pulmonary lesions while three had disseminated disease. Nocardia asteroides was isolated from three patients following bronchoscopy, percutaneous aspirate of a pulmonary lesion in one patients, and from the skin from the aspirates in three patients. Delay in diagnosis in two cases was due to negative microscopy; in one, the diagnosis was made only after repeated bronchoscopy. Of the seven patients, three (43%) died. In two of these, nocardiosis was considered to have directly contributed to death. Co-existent bacterial and viral infections were present in all patients who died. In vitro susceptibility of the organism to co-trimoxazole was variable and did not necessarily reflect clinical efficacy. In one patient, a good clinical response was achieved with co-trimoxazole despite apparently reduced in vitro susceptibility.

Infectious sequelae after endoscopic sclerotherapy of oesophageal varices: role of antibiotic prophylaxis

In order to determine the incidence of infection following sclerotherapy and the role of antimicrobial prophylaxis, a prospective randomized control study was performed comparing i.v. imipenem/cilastatin, with an infusion of dextrose-saline as a control group. One hundred patients with bleeding esophageal varices were included. All episodes of infection were documented during admission to the unit. Ninety-seven patients were evaluable. Post-sclerotherapy bacteremia developed in six (5.6%) of 107 sclerotherapy sessions in the control group and one (1.1%) of the 88 sclerotherapy sessions in the imipenem/cilastatin group (P < or = 0.1, NS): six of these seven post-sclerotherapy bacteremias occurred after emergency sclerotherapy. Infection within 7 days of the procedure was documented after 43 (22.1%) of the 195 sclerotherapy sessions, 18 (20.5%) in the imipenem/cilastatin group and 25 (23.4%) in the control group (P = NS). These infections were significantly more common after emergency sclerotherapy, 40 (34.8%) of 115 sessions, than after elective sclerotherapy, three (3.8%) of 80 sessions (P < or = 0.0001). A short prophylactic antibiotic regime does not reduce the risk of early bacteremia or the frequency of infection after sclerotherapy. The higher risk of infection after emergency sclerotherapy may be therefore related more to the gastrointestinal hemorrhage and its associated effects than to sclerotherapy.

Epidemiology, bacteriology and control of an outbreak of Nocardia asteroides infection on a liver unit

An outbreak of Nocardia asteroides infection affecting seven patients is described. Over a 5-week period, five patients with liver disease admitted to a ward developed clinical and laboratory evidence of nocardiosis, and two further cases were diagnosed 3 and 5 months later. Three out of the five patients who received specific antimicrobial therapy responded to treatment; in three patients nocardia infection was considered to have contributed to death. In six out of the seven patients, nocardiosis followed immunosuppression. A common-source outbreak was considered to be responsible for infection in the first five patients. In two patients, presentation of infection 5 and 7 months after the first case may have been due to prolonged colonization or subclinical infection with Nocardia. Biotyping of the seven isolates using a fluorogenic biochemical method identified three distinct strains of N. asteroides. The most probable source of Nocardia was contaminated brick and plaster dust arising from building work in an area adjacent to the ward. However, samples of air, dust and water failed to yield N. asteroides. Infection control measures included ward closure followed by thorough cleaning, and formaldehyde fumigation.

Salmonella bacteraemia in sickle cell disease at King's College Hospital: 1976-1991.

A review of all blood culture isolates for the 16 years from 1976 were collated with prospective laboratory and clinical records of 620 sickle cell patients treated at Kings College Hospital. Over half of all salmonella bacteraemias diagnosed in the clinical laboratory occurred in sickle cell disease (SCD) patients. Of 21 bacteraemias in SCD patients, 11 (52.3%) were due to Salmonella spp. compared with 23 (0.4%) of 4884 bacteraemias in patients without SCD (P = < 0.00001). In SCD, Gram-negative bacilli were responsible for 16 (76.2%) bacteraemias, of which 11 (68.8%) were due to Salmonella spp. but there were no cases of S. typhi or S. paratyphi. An increase in the number of salmonella infections over the past 5 years were noted in the SCD and non-SCD patients, nine and 16 cases respectively, compared with two and seven cases in the previous decade. However, the recent increase of S. enteritidis phage type 4 in the UK was not evident in SCD patients. These findings have important preventative and therapeutic implications for the management of SCD patients.

Acute Liver Failure: Management of infection in acute liver failure

INTRODUCTION Patients with acute liver failure (ALF) require multiple invasive procedures and are at risk of the wide range of nosocomial and opportunistic infections commonly associated with intensive care. Furthermore, these patients are known to have several immunological defects that increase their suspectibility to infection, and are probably more immunocompromised than other groups of susceptible patients such as those with neutropenia. Study of the efficacy of a variety of antimicrobial strategies to reduce the very high infection-related mortality in ALF patients has resulted in the selection of antimicrobial prophylaxis and therapy for these patients. This has been based upon three important factors: knowledge of the immunological abnormalities present in this condition; the risk factors associated with the clinical management of organ failure; and the incidence, timing and microbiological nature of these infections. NATURE OF DEFECTS IN HOST DEFENSE MECHANISMS Several defects of host immune function arise as a direct consequence of ALF. The liver is the major site of complement synthesis, and reduced levels of serum complement (mainly C3 and C5 components) are found in ALF (Wyke et al. 1980). Low levels of complement correlate with a low opsonization index against bacteria and yeasts, and opsonization is significantly impaired in both children and adults (Wyke et al. 1980; Larcher et al. 1981; Wyke, Yousif-Kadaru et al. 1982). In addition, serum from these patients is a poor chemoattractant for normal polymorphs.

Exogenous Nocardia asteroides endophthalmitis following cataract surgery

We present a case of Nocardia asteroides endophthalmitis following cataract surgery. It is the second to be reported and the first in which vision has been preserved. Symptoms commenced 5 days after surgery and there followed a chronic relapsing anterior uveitis which lasted for 4 months. Nocardia asteroides was finally cultured from an aqueous aspirate and a combination of specific antimicrobial treatment and surgery resulted in a satisfactory visual outcome. Exogenous nocardial intraocular infection is rare and must be distinguished from fungal infection as the organism is resistant to antifungal agents.

Bacterial contamination of fabric and metal-bead identity card lanyards: A cross-sectional study

In healthcare, fabric or metal-bead lanyards are universally used for carrying identity cards. However there is little information on microbial contamination with potential pathogens that may readily re-contaminate disinfected hands. We examined 108 lanyards from hospital staff. Most grew skin flora but 7/108 (6%) had potentially pathogenic bacteria: four grew methicillin-susceptible Staphylococcus aureus, and four grew probable fecal flora: 3 Clostridium perfringens and 1 Clostridium bifermentans (one lanyard grew both S. aureus and C. bifermentans). Unused (control) lanyards had little or no such contamination. The median duration of lanyard wear was 12 months (interquartile range 3-36 months). 17/108 (16%) of the lanyards had reportedly undergone decontamination including wiping with alcohol, chlorhexidine or chlorine dioxide; and washing with soap and water or by washing machine. Metal-bead lanyards had significantly lower median bacterial counts than those from fabric lanyards (1 vs. 4 CFU/cm(2); Mann-Whitney U=300.5; P<0.001). 12/32 (38%) of the metal-bead lanyards grew no bacteria, compared with 2/76 (3%) of fabric lanyards. We recommend that an effective decontamination regimen be instituted by those who use fabric lanyards, or that fabric lanyards be discarded altogether in preference for metal-bead lanyards or clip-on identity cards.