First outbreak of PVL-positive nonmultiresistant MRSA in a neonatal ICU in Australia: comparison of MALDI-TOF and SNP-plus-binary gene typing.

The purpose of this brief report is to describe the first outbreak of a community-associated nonmultiresistant and PVL-positive MRSA strain (CC30) in a neonatal intensive care unit in Australia. The utility of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) for microbial typing is compared with single nucleotide polymorphism (SNP) plus binary gene analysis. The composite correlation index analysis of the MALDI-TOF-MS data demonstrated the similar inter-strain relatedness found with the SNP-plus-binary gene typing used to confirm the outbreak. The evolving spread of MRSA emphasizes the importance of surveillance, infection control vigilance and the ongoing investigation of rapid typing methods for MRSA.

Fistula-in-ano: an unusual presentation of chronic schistosomiasis.

A 30 year old Ethiopian man presented with recurrent perianal abscess and fistula-in-ano. Ova of Schistosoma mansoni were found on fecal microscopy, and were subsequently identified in fibrous tissue excised from the fistula tract. Chronic schistosomiasis should be recognized as a rare cause of fistula-in-ano. Treatment of schistosomiasis with praziquantel may prevent further complications of this condition.

Brucellosis: re-emergence and changing epidemiology in Queensland.

OBJECTIVE: To define the epidemiological and clinical characteristics of human brucellosis, which is being detected in increasing numbers of patients in Queensland. DESIGN AND SETTING: Thirty-four cases of brucellosis diagnosed according to standard clinical and microbiological criteria were studied either retrospectively or prospectively over a two-year period from October 1989 to October 1991. RESULTS: Cases were assessed by means of standard laboratory investigations and a questionnaire documenting clinical symptoms, occupation and recreational activities, treatment and response, relapse rate and complications. Blood cultures taken from 11 patients were positive for Brucella suis; in three others, Brucella suis was cultured from other sites. In the 12 months before diagnosis, all affected individuals were involved in the killing and slaughter of feral pigs. Most infections occurred in rural Queensland but six were contracted in metropolitan Brisbane from feral pig abattoirs. All patients responded to appropriate antibiotic therapy; the relapse rate was 66% in those treated for less than four weeks. Complications (multiple splenic abscesses, epididymitis, cervical lymphadenitis and septic arthritis) occurred in four patients, who were ill for more than one month before diagnosis. CONCLUSIONS: Brucellosis due to Brucella abortus is a disappearing disease in Australia as a result of effective eradication programs in cattle. However, the disease is re-emerging in Queensland because of recreational and occupational exposure to feral pigs infected with Brucella suis. The population at risk is increasing as the lucrative export industry based on field-shot feral pigs expands.

Biotypes of Haemophilus influenzae that are associated with noninvasive infections.

In this study, we examined the biotypes of Haemophilus influenzae strains associated with noninvasive infections in hospitalized patients. Over an 18-month period, a total of 388 strains were isolated from patients of various ages (neonates to the elderly), and the biotypes of the strains were determined. Strains of biotype II accounted for 48% of the isolates; this was followed by strains of biotypes III and I (26 and 16%, respectively). The remaining 10% of the isolates were made up of strains of biotypes IV, V, VI, and VII. A total of 6% of strains were capsulated. The distribution of biotypes in specimens from the respiratory tract and associated sites was comparable to that obtained in similar investigations, but examination of isolates from neonatal and genital specimens did not support the concept that H. influenzae biotype IV is a major urogenital pathogen. Conflicting results regarding the incidence of certain biotypes in specimens, particularly those from the urogenital tract, may be due to the selection of different subpopulations of patients. Data relating to the specimens were used to evaluate the association between biotype and clinical diagnosis, the presence of other potential bacterial pathogens in the specimens, and the presence of viruses in the specimens. None of the differences in the distribution of biotypes which were examined was statistically significant.

Branhamella (Moraxella) catarrhalis: pathogenic significance in respiratory infections.

OBJECTIVES: To assess the pathogenic significance of Branhamella catarrhalis isolates in patients with respiratory infections and to define the clinical characteristics of such patients. DESIGN AND SETTING: Respiratory specimens were assessed in a three-year prospective study performed in a Brisbane metropolitan hospital. Assessment of the pathogenic significance of isolates of B. catarrhalis was based on four predetermined criteria: (i) clinical evidence of respiratory infection based on history, examination and chest x-ray; (ii) isolation of B. catarrhalis as the sole potential pathogen; (iii) absence of antibiotic treatment in the previous two weeks; and (iv) subsequent clinical response to an antibiotic to which the isolate was sensitive. RESULTS: B. catarrhalis was identified in 118 respiratory samples, 92 (78%) being from patients less than 10 years old. Infection with B. catarrhalis was more commonly seen in winter months and was community-acquired in two-thirds of cases. Isolation of this organism was associated with a broad variety of upper and lower respiratory tract syndromes. Isolates were considered to be of pathogenic significance (all four above criteria satisfied) in 35% of cases and of possible significance (the first and fourth criteria satisfied) in a further 15% of cases. Isolates were more likely to be of pathogenic significance in older patients and in those with pre-existing cardiorespiratory disease; however, a number of serious infections were observed in previously-well children. Expectorated sputum and tracheal aspirates were more likely to yield a clinically significant isolate than nasopharyngeal aspirates. Production of beta-lactamase was demonstrated in 88% of isolates. CONCLUSION: B. catarrhalis causes respiratory infection more frequently than is generally appreciated. Isolation of this organism from the respiratory tract had pathogenic significance or possible pathogenic significance in 50% of our patients. If therapy is indicated in patients with respiratory infection caused by this organism, traditional beta-lactam regimens cannot be relied upon, as shown by the high rate of beta-lactamase production in this study; a tetracycline, erythromycin, a second or third generation cephalosporin, or the combination of a penicillin derivative and beta-lactamase inhibitor should be considered.

Bacteremia caused by Mycobacterium neoaurum.

An immunocompromised patient with an indwelling Hickman catheter developed Mycobacterium neoaurum bacteremia. This rapidly growing mycobacterium was previously isolated from soil, dust, and water but has not been described as a human pathogen. The infection responded to therapy with cefoxitin and gentamicin. It was not necessary to remove the Hickman catheter.

Blood cultures in hospitalized children.

The results of 2439 blood cultures that were taken in an acute children's hospital over a two-year period were reviewed. Three hundred and twenty-two organisms were cultured from 310 patients. One hundred and thirty-five (5.5%) isolates were considered to be pathogenic and 187 (7.7%) isolates were considered to be contaminants. Coagulase-positive staphylococci and enteric Gram-negative organisms were the isolates of which the significance was most difficult to determine. Community-acquired bacteraemia that affected children of less than five years of age was caused by Haemophilus influenzae in 65% of cases. Staphylococcus aureus was the major pathogen in older children. In 20% of cases, antimicrobial agents were commenced or changed after blood culture results. Delayed or inappropriate therapy was significantly more common in patients without an apparent focus of infection. The results of our study suggest that narrow spectrum antimicrobial agents can be used as appropriate empiric therapy for unlocalized infections in previously-well children. In children of between three months and five years of age, treatment should be directed against Haem. influenzae and Streptococcus pneumoniae, and in children of over five years of age, antistaphylococcal therapy should also be included.

Mycetoma associated with Acremonium falciforme infection.

A patient from Vanuatu with a mycetoma of the foot of 25 years' duration is described. Culture of a biopsy specimen from the foot grew a fungus which was identified as Acremonium falciforme. This agent has not been described previously in association with mycetomas in the Pacific region.

Isolation of Campylobacter fetus from blood cultures.

Campylobacter fetus subsp. fetus, previously known as Campylobacter fetus subsp. intestinalis, was isolated from two blood cultures taken from a 45-year-old man admitted with gastrointestinal symptoms and a history of lymphocytic lymphoma. Campylobacters are not common blood culture isolated but can be a cause of bacteraemia and septicaemia especially in the compromised host. The isolation and identification of Campylobacter fetus subsp. fetus by standard blood culture techniques is described and a literature review of 112 cases of campylobacter bacteraemia is presented.