Reducing methicillin-resistant Staphylococcus aureus (MRSA) patient exposure by infection control measures

INTRODUCTION: To assess the effectiveness of infection control measures (pre-admission screening and patient segregation) on reducing in-patient exposure to methicillin-resistant Staphylococcus aureus (MRSA). PATIENTS AND METHODS: A prospective case-control study in a district general hospital. All admissions to 3 wards over an 83-month period from September 1995 to July 2002 inclusive (a total of approximately 34,000 patients). Outcome measures were a statistical analysis of the difference in numbers of new cases of MRSA colonisation or infection between the 3 wards. RESULTS: There was a statistical significance in incidence of new MRSA cases between the ward with active infection control measures in place and the control wards. CONCLUSIONS: The described infection control measures reduced the exposure of patients to MRSA. This reduces the risk of MRSA infection, which is of importance in orthopaedics, and has further benefits that may also be applied in other surgical specialties.     

An update of the etiology and management of xerostomia

Salivary gland disease gives rise to salivary gland enlargement, pain, and prolonged xerostomia (dry mouth). Xerostomia is the most common long-standing problem for the majority of affected patients. There are many causes of dry mouth, with long-standing xerostomia being a particular problem in Sj?gren's syndrome and after radiation to the head and neck region. Xerostomia is usually managed with saliva substitutes, but a large number of potential systemic therapies of long-standing xerostomia now exist. Some-particularly immunosuppressants-are of fundamental interest for the potential reduction of gland damage in Sj?gren's syndrome but as yet are of limited clinical usefulness. Others, particularly pilocarpine and cevimeline, are, or have the potential to be, clinically useful in stimulating salivation by virtue of their action on cholinergic receptors.     

Airway intervention in adult supraglottitis

Background The timing of aggressive airway intervention in adult epiglottitis is controversial. Aims To correlate Friedman’s staging of epiglottitis on admission with the airway interventions undertaken. Methods A retrospective study of 23 adult patients, mean age 51 years (range 29–81 years), who had been admitted with acute supraglottitis between March 1988 and December 2000 was undertaken. Results Three patients (13%) had airway interventions; two with tracheostomy and one with tracheal intubation. All were Friedman stage III and had rapid symptom progression during the 24 hours prior to admission. Three other stage III patients with symptom progression longer than 24 hours and all the remaining patients (stage II or less) were managed with observation and intravenous therapy. Conclusions Friedman originally advocated airway intervention in any patient stage II or worse, but this intubation threshold should probably be lowered to those patients with rapid-onset stage III (moderate respiratory distress, stridor, respiratory rate >30 per minute, pCO₂ >45mmHg) disease.     

Ectopic ossification in the parotid gland

We present a unique report of ectopic ossification with dystrophic calcification within an otherwise histologically normal parotid gland. The histopathological features of the case are discussed and general pathogenetic explanations for the lesion are explored.     

In vitro evidence for the presence of hematopoietic stem cells in the adult human liver

Previous studies have identified novel lymphoid phenotypes in the adult human liver and provided evidence to suggest that lymphoid differentiation can occur locally in this organ. The aim of this study was to examine the adult human liver for the presence of hematopoietic stem cells that may provide the necessary precursor population for local hematopoietic and lymphoid differentiation. Hepatic mononuclear cells (HMNC) were extracted from normal adult liver biopsy specimens using a combination of mechanical disruption and enzymatic digestion. The stem cell marker CD34 was found on 0.81% to 2.35% of isolated HMNCs by flow cytometry. CD34(+) HMNCs were positively selected using magnetically labeled beads, and the enriched population was further examined for surface markers characteristically expressed by immature hematopoietic cells and early progenitors. CD45 was expressed by 49% (+/-23%) of CD34(+) HMNCs, indicating their hematopoietic origin. CD38, one of the first markers to be expressed by developing progenitor cells was found on 50% (+/-22%) of CD34(+) HMNCs indicating the presence of both pluripotent stem cells and committed precursors. The majority (90%) of CD34(+) HMNCs coexpressed the activation marker human leukocyte antigen DR, consistent with actively cycling cells. Functional maturation of these hepatic progenitors was shown by the detection of multilineage hematopoietic colony formation after tissue culture. Erythroid (BFU-E), granulocyte-monocyte (CFU-GM), and mixed colonies (CFU-GEMM) were detected after culture of unseparated HMNCs and the enriched CD34(+) HMNC population; 14.3 +/- 13.2 (mean +/- SD) BFU-E, 3.1 +/- 3.1 CFU-GM, and 0.4 +/- 0.9 CFU-GEMM per 1 x 10(5) unseparated HMNCs and 16.0 +/- 9.5 BFU-E and 1.7 +/- 0.9 CFU-GM were identified per 2.4 x 10(3) CD34(+) HMNCs plated. The detection of surface markers characteristic of immature hematopoietic cells and colony formation in tissue culture provides evidence for the presence of hematopoietic stem cells and early progenitor cells in the adult human liver. This would suggest that the adult human liver continues to contribute to hematopoiesis and may be an important site for the differentiation of lymphohematopoietic cells involved in disease states, such as autoimmune hepatitis and graft rejection after liver transplantation.     

Detection of carbamyl phosphate synthetase 1 deficiency using duodenal biopsy samples

The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives.     

Controlled trial of continuous inflating pressure for hyaline membrane disease

A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131).