Wounds scrutiny in a Swedish hospital: prevalence, nursing care and bacteriology, including MRSA.

OBJECTIVE: To identify all wounds, wound types and wound characteristics; to identify bacteria in all wounds, particularly MRSA, VRE and multi-resistant Gram-negative rods;. METHOD: All patients admitted to or visiting hospital clinics were examined. If the patient had a wound, a questionnaire was filled in by a nurse, and if the wound met the inclusion criteria swabs were taken. RESULTS: A total of 2172 patients were admitted to or visited the hospital; 408 (19%) had a total of 668 wounds. Of this number, 248 were cultured. Thirty-seven patients had pressure ulcers, 83 had leg and foot ulcers and 288 patients had other types of wounds. Nursing care varied according to wound type and ward. Fifty-eight different types of wound dressings were used. Cleansing was performed with saline in 58% of the wounds. The mean number of dressing changes was once daily. Wounds were painful in 37% of the cases, with a predominance of leg and foot ulcers (51%). Many patients did not receive analgesia. MRSA was identified in two patients. No VRE was identified, and there was a low prevalence of multi-resistance in Enterobacteriaceae and Pseudomonas aeruginosa. CONCLUSION: The study provided important information for future improvement of wound care in a university hospital. Fewer resistant bacteria, particularly MRSA, were identified than expected.

RAPD-PCR and PFGE as tools in the investigation of an outbreak of beta-haemolytic Streptococcus group A in a Swedish hospital.

We evaluated the random amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) techniques for studying an outbreak of beta-haemolytic streptococci group A (GAS) occurred at two maternity wards at Danderyd hospital, Stockholm, Sweden. All the isolates were of T-type 8,25. The RAPD technique revealed that all RAPD-PCR profiles were identical. PFGE showed that all the patterns but one were identical. These patterns were compared with 10 different T-type GAS from the strain collection of the Swedish Institute for Infectious Disease Control (SMI) and T-type 8,25 from different years and locations. The SMI strains exhibited patterns different from each other and all different from the isolates from Danderyd hospital. Moreover, RAPD could not differentiate among the T-type 8,25 isolates from different years and locations but PFGE showed differences among the amplicons. Our results indicated that the RAPD and PFGE techniques could be efficient tools in epidemiological studies of GAS.

Influence of wearing masks on the density of airborne bacteria in the vicinity of the surgical wound.

To find out if the wearing of masks influenced the number of colony forming units (CFU) of bacteria in the vicinity of the wound, 14 operations on the thyroid gland were divided in 30 min periods during which personnel were randomly allocated to wear or not to wear masks. There was at least one period with, and one without masks during each operation. Air was sampled 20 cm from the wound using a Sartorius membrane filter sampler. There were no significant differences between the groups in either numbers of CFU or species of pathogenic bacteria found.

Air contamination during hip and knee arthroplasties. Horizontal laminar flow randomized vs. conventional ventilation.

In a randomized study 90 patients, operated on with a total hip or knee arthroplasty, were allocated to 1 of 3 different regimes, all including a reinforced single-use operating gown: (1) horizontal laminar flow ventilation and conventional clothes (cotton shirts and trousers) for all staff members, (2) horizontal laminar flow ventilation and occlusive garments (Klinidress) and (3) conventional ventilation and occlusive garments. Volumetric air sampling gave a low mean number of colony-forming units (< 10 cfu/m3) in the vicinity of the wound in all 3 groups. Laminar ventilation, with or without occlusive staff garments, resulted in less air contamination compared to conventional ventilation. During knee arthroplasty, the use of occlusive clothes in the laminar ventilation room, further reduced the number of airborne, bacteria-carrying particles to around 1 cfu/m3. No such reduction was seen during hip arthroplasty. We conclude that hip and knee arthroplasties can be performed in operating theaters with conventional ventilation when occlusive staff garments are used. However, laminar air flow ventilation in knee surgery, preferably in combination with occlusive garments, resulted in a substantially lower air contamination and should be preferred.

Immunochemistry of Salmonella O-antigens: specificity of rabbit antibodies against the O-antigen 2 determinant elicited by whole bacteria and 3-O-alpha-paratopyranosyl-D-mannopyranosyl conjugated to bovine serum albumin.

The binding specificities of antibodies directed against the Salmonella sero-group A-specific O-antigen 2 determinant were characterized by precipitation-inhibition and enzyme-linked immunosorbent assay inhibition tests. Two different antigen O-2-specific antisera were investigated: one conventional factor O-2 serum (elicited by whole heat-killed Salmonella paratyphi A bacteria) and another elicited by the synthetic disaccharide 3-O-a-paratopyranosyl-D-mannopyranosyl (formula: see text) covalently linked via a p-isothiocyanatophenyl aglycon to bovine serum albumin (PM-BSA). The inhibition data showed that factor O-2 antibodies have combining sites which recognize structures larger than the (formula: see text) disaccharide and equal to or smaller than an O-antigen O-2-specific octasaccharide derived from the S. paratyphi A O-polysaccharide. Although the factor O-2 serum exhibited a high specificity for the homologous S. paratyphi A O-antigen it still precipitated, though weakly, a heterologous Salmonella typhimurium O-antigen. In contrast, anti-PM-BSA antibodies were exclusively specific for the O-2 determinant of the native polysaccharide antigen. The combining sites of these antibodies best recognized the (formula: see text) disaccharide, including the linkage arm and the lysyl residue of the BSA carrier protein molecule. These data extend earlier findings as to the superior specificity of anti-PM-BSA antibodies as compared to conventional factor O-2 antibodies.

Diagnosis of Salmonella infections: specificity of indirect immunofluorescence for rapid identification of Salmonella enteritidis and usefulness of enzyme-linked immunosorbent assay.

An indirect immunofluorescence (IFL) method was used for diagnosis of infections caused by Salmonella enteritdis during an epidemic. Antiserum prepared against the synthetic disaccharide tyvelose 1 leads to alpha 3 D-mannose, representative of salmonella O antigen 9, covalently linked to bovine serum albumin, was used. Of 43 decal samples examined, 28 were positive for S. enteritidis by culture. IFL was applied (1) directly on fecal smears, (2) on enrichment broth cultures after incubation for 18-24 hr, and (3) on agar-grown colonies after incubation for 18-48 hr. The percentage of correctly identified Salmonella and the approximate gain of time for IFL as compared with conventional culture were 75% and 72 hr for (1), 89% and 48 hr for (2), and 100% and 24 hr for (3). Serum samples from 26 of the Salmonella-infected patients were examined by an enzyme-linked immunosorbent assay (ELISA). Twenty-four (92%) of the 26 patients acquired elevated ELISA titers of antibody to lipopolysaccharide, representative of Salmonella serogroup D.

Artificial Salmonella vaccines: Salmonella typhimurium O-antigen-specific oligosaccharide-protein conjugates elicit opsonizing antibodies that enhance phagocytosis.

Outbred NMRI mice and rabbits were vaccinated with different artificial Salmonella typhimurium immunogens and the specificity and activity of elicited antibodies were studied in in vivo and in vitro phagocytosis assays. The Salmonella immunogens used were: (i) the synthetic disaccharide, abequose (formula see text) D-mannose, representative of Salmonella O antigen 4, covalently linked to bovine serum albumin (BSA); (ii) the octa- and dodecasaccharides, (formula see text) covalently linked to BSA; and (iii) whole heat-killed Salmonella. Rabbit antibodies passively administered to mice significantly enhanced the clearance of intravenously injected S. typhimurium challenge bacteria from the bloodstream. The clearance rate and the titer of anti-O-antigen-specific antibodies correlated. The clearance rate of an S. thompson (O6,7) strain, which has a different O antigen, was the same irrespective of the rabbit serum given. NMRI mice actively immunized with the various oligosaccharide-BSA conjugates had a significantly increased clearance rate of S. typhimurium only. In the in vitro assay, mouse antioligosaccharide-BSA sera promoted phagocytosis of S. typhimurium, but not S. thompson, when incubated with complement and mouse peritoneal exudate cells activated with Freund complete adjuvant.

Respiratory tract colonization and infection in patients with chronic tracheostomy. A one-year study in patients living at home.

The high rate of complications, especially respiratory tract infection (RTI), reported in patients with chronic tracheostomy (CT) has discouraged physicians from using this method. However, previous studies of CT have concerned mainly hospitalized patients. We have followed the bacterial colonization patterns of the upper and lower respiratory tract and recorded all RTIs in 39 outpatients with CT during a 12-mo period. Patients were colonized with one or more potential pathogens at the stomal site and in the trachea in 95% and 83%, respectively, of all sampling occasions. Staphylococcus aureus, gram-negative enteric bacteria (GNEB), and Pseudomonas aeruginosa were the most common colonizing bacteria at these sites. Seventy percent of bronchial-protected brush cultures were negative, despite simultaneous heavy colonization of the stomal site or the trachea. Only 18 of 39 (46%) patients were treated with antibiotics because of RTIs on a total of 30 occasions during the study year. Of these, only five episodes of pneumonia in four patients were registered, corresponding to an incidence of about 10 per 100 person years. We conclude that outpatients with chronic tracheostomy can be managed with a low risk for developing severe RTIs, despite massive airway colonization with potentially pathogenic bacteria.

Clinical manifestations of Borrelia infections of the nervous system.

Clinical, treatment and laboratory parameters were analyzed in 46 consecutive Swedish patients with Borrelia infections of the nervous system. The importance of age in the clinical symptoms, the wide spectrum of disease, and the chronic behaviour of the Borrelia infection of the nervous system was stressed, as well as the benefit of high-dose intravenous antibiotics, especially penicillin G. Borrelia infection of the nervous system can imitate other diseases. When associated with meningitis it can mimic psychosomatic disorders, when associated with radiculoneuritis it may imitate herniated discs and when central nervous involvement of the Borrelia infection occurs, it can mimic a non-infectious, thrombotic or haemorrhagic cerebro-vascular disease.

Tick-borne Borrelia-meningitis in children. An outbreak in the Kalmar area during the summer of 1984.

Nine children, aged 5 to 11 years, with subacute or chronic meningitis were studied. Symptoms started during the summer season in all patients and in eight of the patients the disease began with a localized erythematous lesion (ECM), mostly in the face. In one patient only there was a history of an insect bite at the site of the erythema. The neurological abnormalities included aseptic meningitis, peripheral facial nerve palsy (5/9) and oculomotor nerve palsy (1/9). Most children complained of headache, fatigue, loss of appetite and had a low grade fever. High antibody titers to Borrelia spirochetes in serum and/or cerebrospinal fluid (CSF) were demonstrated by ELISA in eight of the nine patients and by indirect immunofluorescence assay (IFA) in three patients. All patients had a dramatic improvement in their general condition and became afebrile within three days of institution of i.v. penicillin G treatment (i.v. cefuroxime in one patient).

Erythema chronicum migrans in Sweden: clinical manifestations and antibodies to Ixodes ricinus spirochete measured by indirect immunofluorescence and enzyme-linked immunosorbent assay.

26 Swedish patients with erythema chronicum migrans (ECM) were studied regarding associated clinical symptoms and antibodies to Swedish Ixodes ricinus spirochete. 11/26 (42%) of the patients had associated symptoms, compared to more than 90% of 314 American patients with ECM, as described by Steere et al. Only 2/26 (8%) had multiple skin lesions, compared to 48% of the American patients. Elevated erythrocyte sedimentation rate and circulating immune complexes were demonstrated in 6/25 (24%) and 8/25 patients (32%), respectively, as against in 53% and 84%, respectively, of the American patients. The antibody response to Ixodes ricinus spirochete was measured by indirect immunofluorescence (IFA) and enzyme-linked immunosorbent assay (ELISA). Compared to the 95% percentile of controls, significantly high antibody titers were demonstrated in 3/25 (12%) by IFA, and 7/25 (28%) by ELISA. The ELISA antibody titers differed significantly (p less than 0.05) between ECM-patients and controls. The spirochetal antibody response in ECM was also compared with that in spirochete-associated disease of the central nervous system.

The diagnostic value of enzyme immunoassay and immunoblot in monitoring eradication of Helicobacter pylori.

55 patients with severe ulcer disease and H. pylori infection, successfully treated with antimicrobials, were followed-up with repeated blood samples for up to 32 months. Sera were analysed by enzyme immunoassay (EIA) for IgG and IgA antibodies and by IgG immunoblot. The EIA for IgG antibodies showed a high sensitivity (100%), while IgA antibodies above the cut-off level were found in 55% of the patients. At a median of 77 days after onset of treatment, approximately 50% of the patients showed a significant decrease (> or = 50%) of IgG or had titres below the cut-off level. All patients but 1 had a significant decrease of IgG after 6-12 months. The decrease was slower for IgA. The H. pylori-specific 116 kDa and 19.5 kDa bands were found in all pre-treatment samples, but the decrease in median intensity of the bands was slower than for the IgG EIA. In the 32-months post-treatment samples, both bonds had an intensity still above 50% of the pre-treatment value. The study showed that the IgG EIA is a useful method for monitoring eradication of H. pylori. Immunoblot can detect previous H. pylori infection in EIA negative Individuals.