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Mycobacterium asiaticum was isolated from fluid aspirated from an olecranon bursa that had become inflamed following a superficial injury. Other possible causes of the inflammation were excluded. No specific antimycobacterial therapy was given. The infection responded to drainage, regular dressing, and immobilization. Our experience suggests that M. asiaticum is a potential cause of infection of the joints and surrounding tissues.

During a twelve-month period (1 July 91-30 June 92), feces from 912 persons from the Townsville region in the dry tropics of Queensland, Australia were evaluated by culture and 45 (4.9%) immunocompetent patients were found to be carrying Aeromonas in their stools. All patients were index cases and no secondary cases from household or close contact of index cases were identified. Eight patients (9.3%) were from Palm Island, an Aboriginal community, and 37 (4.5%) were from the essentially Caucasian population of Townsville. This is a significant difference in incidence of cases between the two population groups. Infection occurred mainly in two age groups: the under five-year-old (27 cases) and the over 25-year-old age group (17 cases). Except for one patient, all cases of Palm Island Aborigines were children less than five years of age, and 13 of these infants (48%) were less than 1 year old, but none were neonates. Of the 37 Townsville patients, 20 cases (54%) were in the under five-year-old group. Signs and symptoms of Aeromonas-associated diarrhea in patients where Aeromonas was the sole pathogen isolated were diarrhea sometimes with vomiting, absence of fever and of fecal leukocytes and blood in the stools. No cases of Aeromonas-associated diarrhea with dysentery were encountered. After rotavirus (12.3%), Aeromonas was the second most common enteric pathogen detected, but was only marginally more common than Giardia and Salmonella. Of the aeromonad isolations, 50% were Aeromonas hydrophila, 22% were A. sobria, and 28% were A. caviae.(ABSTRACT TRUNCATED AT 250 WORDS)

During a 12-month period, the clinical spectrum of extraintestinal disease due to Aeromonas species was determined for 56 patients in tropical Queensland (Australia). Forty-six patients acquired their infection in the community, six patients were infected in the hospital, and four patients were colonized. Demographic risk factors included male gender (67%) and Aboriginal ethnic background (35%). The disease ranged from deep-seated infection (four cases) to soft-tissue infection of varying intensity (48 cases). Among patients whose infections were community acquired, 22 required hospitalization and 27 suffered trauma-associated infection. Seventeen patients (63%) in the latter group had lacerations to the hands and feet that were contaminated with surface water or soil. The appearance of the wounds was not pathognomonic, and diagnosis was made by laboratory evaluation. Aeromonas was the sole pathogen in nine patients. Polymicrobial infections were due to Aeromonas and mainly Staphylococcus aureus and/or mixed enteric bacteria. Aeromonas hydrophila was the most common species isolated (71%), followed by Aeromonas sobria (25%). In nine cases, the empirical antibiotic regimen prescribed did not adequately cover infection due to Aeromonas. Infection was seen regularly throughout the year, but a cluster of cases also occurred during the tropical Australian wet season.

Greater than 90% of 131 strains of Aeromonas species were susceptible to the aminoglycosides, ureidopenicillins, extended-spectrum cephalosporins, aztreonam, quinolones, tetracycline, and chloramphenicol, and all were uniformly resistant to ampicillin. Except for amoxicillin-clavulanate, sulfonamide, trimethoprim, and trimethoprim-sulfamethoxazole, there was good correlation between the results obtained by the agar dilution and disk diffusion techniques.

Three selective enrichment broths and four selective agar media were evaluated for their ability to support the growth of Pseudomonas pseudomallei both at 35 degrees C and at ambient temperature (range, 20 to 32 degrees C; mean, 25 degrees C). Colony counts of 50 strains of P. pseudomallei and recovery studies with 1 soil strain in 60 simulated soil samples demonstrated that enrichment with Trypticase soy broth incorporating 5 mg of crystal violet per liter and 20 mg of colistin per liter (CVCB) and subculture to Ashdown medium supported the growth of all 50 strains and produced the highest recovery rates with the greatest suppression of other soil flora. An enrichment broth of MacConkey broth (purple) incorporating 10 mg of crystal violet per liter, 5 mg of bromcresol purple per liter, 25 mg of gentamicin per liter, and 650 mg of streptomycin per liter showed greater suppression of soil bacteria than CVCB, but it failed to support the growth of three strains of P. pseudomallei. Recovery rates were essentially the same irrespective of whether the soil samples were incubated at 35 degrees C or at ambient temperature, provided cultures were incubated in protected shade for an extended period. This is an important feature for field work in large-scale epidemiological surveys in which resources are limited.

Objective: To report the first human case of autochthonous melioidosis in temperate Australia (latitude 31 degrees 10'S) and to describe the extent of the presence of the causative agent, Pseudomonas pseudomallei, in southwest Western Australia., Clinical Features: A 45-year-old man living on a hobby farm was admitted to hospital for investigation of lung lesions, weight loss and low grade fevers. P. pseudomallei was cultured from material from an aspiration biopsy of a mediastinal mass., Intervention and Outcome: The patient was successfully treated with a regimen of ceftazidime and trimethoprim-sulfamethoxazole. A review of epidemiological data showed that, since 1967, P. pseudomallei has been cultured from animals and soil in a region 50-250 km north-west of Perth, Western Australia, and that pockets of endemicity are found in the districts of Toodyay (where our patient's farm was), Chittering, Ballidu, Gidgegannup, Badgingarra, and Wongan Hills., Conclusion: The persistence of the bacterium in animals and soil in south-west Western Australia demonstrates abundantly that P. pseudomallei can exist opportunely beyond its traditional tropical habitat. It is likely that there will be further clinical cases of melioidosis originating in this region, and that the boundaries of endemicity in Australia will expand further.

Human infection with Pseudomonas pseudomallei, the causative agent of melioidosis, typically produces subclinical disease and an asymptomatic carrier state; occasionally clinical illness, frequently with a fatal outcome, may occur. Consequently, to help protect staff from laboratory-acquired melioidosis, microbiological and biomedical laboratories must have adequate facilities for safe work procedures and laboratory staff must engage in safe work practices. Recommendations from a melioidosis-endemic, diagnostic laboratory for the prevention of laboratory-acquired infection with this bacterium are essentially Category 3 (Advisory Committee on Dangerous Pathogens), Risk Group 3 (Australian Standards) or Biosafety Level 2 (National Institutes of Health) precautions. These include safeguards for centrifugation, prohibiting the 'sniff' test and the use of a biological safety cabinet for sputum processing, for subculture of stock strains, for preparation of antigen and for research studies but not for routine diagnostic techniques with P. pseudomallei.

The Minitek disc system was utilized for the differentiation of Pseudomonas pseudomallei, the causative agent of melioidosis, from Ps. cepacia. The system was simple to use, inexpensive, and furnished rapid, clear-cut test results after 4 h. This procedure is suitable for differentiating soil bacteria presumptively identified as Ps. pseudomallei, Ps. cepacia or flavobacteria, and for the rapid confirmation of the presumptive identification of either Ps. pseudomallei or Ps. cepacia obtained by commercial identification-kit systems in the clinical laboratory.

By using enzyme immunoassay and immunofluorescence antigen detection techniques on sputum specimens, four of 260 patients with pulmonary infection resident in tropical Queensland were found to be infected with Chlamydia. All four chlamydial infections were community-acquired and there was no history of close contact with birds by any of the four patients. One woman was deemed to be suffering with Chlamydia pneumonia, while the role of the organism in the pathogenesis of respiratory disease in the other three patients was indeterminate. At present, the incidence of pulmonary chlamydial infection in the population of tropical Queensland does not warrant routine testing, but investigations for these organisms should be undertaken in patients who present to their physicians with atypical pulmonary infection or whose clinical conditions are refractory to penicillin/ampicillin therapy.

Of 46 patients with clinical melioidosis, 35 (22 culture-positive and 13 culture-negative) had relatively uneventful disease courses, with elevated serum C-reactive protein (CRP) concentrations (greater than 5 mg/dl) that decreased with the commencement of appropriate antibiotic therapy, and continued to show an uninterrupted decrease (mean 29.4 days, range 12-52 days) to the normal range (less than 1 mg/dl), with resolution of their infections. In five culture-positive patients with complicated disease courses, CRP concentrations remained elevated (greater than 5 mg/dl) until the underlying disorders were successfully managed, or until the antibiotic regimen was changed, and CRP values then decreased to the normal range. During surveillance, elevated CRP concentrations (greater than 10 mg/dl) led to the diagnosis of reactivation of infection in three afebrile patients, while the serum CRP values in other patients remained within the normal range in the absence of intercurrent complications. The CRP estimations may be helpful in ascertaining active infection in patients with low serum levels of specific IgM antibody, and serial measurements of serum CRP in patients with clinical melioidosis may be useful in determining the optimal duration of treatment and for detecting occult or unresolved infection with Pseudomonas pseudomallei.

Objective: To describe the clinical presentation, diagnosis and management of strongyloidiasis in northern Queensland, and to identify predisposing factors for this infection., Design: A five-year retrospective study of medical records of all cases diagnosed in a regional hospital microbiology laboratory, with follow-up by interview where possible., Setting: The Townsville General Hospital., Patients: A total of 14 cases of strongyloidiasis were identified, with patients ranging in age from 7 months to 59 years., Results: Infected patients included nine Aborigines and two Vietnamese refugees, both high-risk groups. Of three Caucasians diagnosed, one was a war veteran, but the other two did not have significant travel histories; all three had lived or worked under insanitary conditions. In only one case was strongyloidiasis suspected; in most, it was diagnosed because of diarrhoea or blood eosinophilia which could not be related to the presenting illness. Thiabendazole treatment was effective in most cases., Conclusion: In northern Australia, strongyloidiasis can be acquired locally by Caucasians who live in unhygienic circumstances. It should be suspected in any person with unexplained abdominal pain, diarrhoea, cutaneous symptoms or blood eosinophilia, and the laboratory must be informed of the provisional diagnosis.

Objective: To report the success of hyperbaric oxygen therapy in the treatment of Nocardia brasiliensis mycetoma. We believe this to be only the second report in the medical literature of hyperbaric oxygen therapy used in the therapy of nocardial disease., Clinical Features: A 78-year-old man presented to a general hospital outpatient clinic after eight months with a painless swollen left foot. There was no significant medical history, no trauma had occurred, and no foreign body had been detected. The dorsum of the foot had a discharging sinus, from which N. brasiliensis was isolated., Interventions: After unsuccessful treatment with surgical debridement and high-dose antibiotic therapy, hyperbaric oxygen therapy was administered in a multiplace recompression chamber (one hour of treatment at 1.8 atmospheres absolute followed by a 30 minute "ascent" to surface pressure). A total of 19 treatments were administered., Outcome: Successful healing of an N. brasiliensis mycetoma of the left foot., Conclusion: In this case of N. brasiliensis mycetoma involving the lower extremity, the conventional management of surgery and antibiotic therapy was unsuccessful, and only with the addition of hyperbaric oxygen therapy did clinical recovery occur.

One hundred clinical isolates of Pseudomonas pseudomallei from humans were tested for their ability to produce extracellular, biologically active substances which are thought to contribute to the virulence of Pseudomonas species. All isolates produced at least on extracellular enzyme; 91 strains were positive for lecithinase, lipase, and protease; but none was positive for elastase. Ninety-three strains produced a hemolysin which was detectable around the heavy growth on saline-washed sheep erythrocyte brain heart infusion agar but not demonstrable around individual colonies or in broth culture filtrate. In contrast, a hemolysin which was cytolytic around individual colonies of P. pseudomallei on the assay plate and in broth culture filtrate was exhibited by four strains. By using one of these four isolates as the test strain, the latter hemolysin was characterized further. It was heat labile, most active in an acid environment (pH 5.5), and cytolytic in broth culture filtrate for a variety of animal and human erythrocytes. Sterols, particularly cholesterol and 7-dehydrocholesterol, inhibited its hemolytic activity, but the activity was not enhanced by reducing agents or suppressed by reagents which modify sulfhydryl-activated hemolysins. A nonhemolytic mutant of the test strain of P. pseudomallei retained the extracellular enzymes of its parent, indicating that the hemolysin was not a lecithinase, lipase, or protease.

Salmonella virchow is the second most commonly isolated salmonella serotype from human sources in Australia, and overseas studies indicate that S. virchow is a significant cause of extraintestinal salmonellosis. The successful management of three infants, two with septicaemia and one with leptomeningitis and septicaemia due to S. virchow, is described. A review of the Townsville General Hospital laboratory records (1978-1988) showed that, among other aspects, S. virchow accounted for 46% of all salmonella septicaemias, further exemplifying the invasive propensity of this serotype. Information obtained from various sources, after crude analyses, demonstrates that more than 90% of S. virchow infections in humans in Australia occur in Queensland, and that most (greater than 78% in 1987) of those infections in Queensland come from a coastal zone north of Bundaberg, with the highest concentration (0.4 per 1000 persons) occurring in the Cairns region.

Three selective isolation media and the paraffin baiting technique were compared with conventional culture (Sabouraud dextrose agar without antibiotic supplement) for the ability to grow and detect nocardiae from simulated sputum specimens. Modified Thayer-Martin medium, incorporating vancomycin, colistin, nystatin and trimethoprim as selective agents, produced the highest recovery rate and with the greatest suppression of normal respiratory tract flora. A clinical evaluation using a screening programme devised for a busy diagnostic microbiology laboratory was performed on 1600 sputum specimens. Inoculating sputum on modified Thayer-Martin medium and extending the initial incubation period of 3 days at 35 degrees C under 10% carbon dioxide to a further 3 weeks at room temperature in a candle jar, led to the diagnoses, which otherwise would have been missed, of pulmonary nocardiosis in 3 patients and pulmonary infections due to Neisseria meningitidis, Pseudomonas cepacia, and Serratia marcescens in a further 22 patients.

During the five-month wet season of 1977-1978 in Northern Queensland, six patients with bacteriologically proven melioidosis were successfully treated at the Townsville General Hospital, The clinical course and management of each case and laboratory findings are described. Factors which predisposed them to infection with Pseudomonas pseudomallei were diabetes mellitus, cancer, alcoholism, malnutrition, trauma, and pregnancy. Successful treatment of melioidosis relied on prompt laboratory diagnosis and appropriate chemotherapy together with surgical drainage of abscesses and management of concomitant diseases. The incidence of melioidosis in Northern Queensland has increased to the extent that it can no longer be considered a rare disease in this area. Because of increased internal and international travel, and displacement of refugees from endemic areas of Southeast Asia, physicians and microbiologists must maintain a high index of suspicion of melioidosis when dealing with patients after geographic exposure, as it is probable that, in the future, this disease witll be encountered more frequently in non-endemic areas.

The development of a human milk bank with nursing mothers as donors of human milk is described. Breast milk is collected manually, and as aseptically as possible, by the mother in the privacy of her home, and the milk is transported frozen to the milk bank by a member of the Nursing Mothers' Association of Australia. A sample of expressed milk is also collected and sent to the Microbiology Department of the Australian Government Health Laboratory for bacteriological examination. The milk bank is suitably located in the paediatric ward of the Townsville General Hospital. Human milk which has been classed as bacteriologically safe is given untreated to hospitalized infants in preference to formula milk. The result is a human milk bank which is administered under medical and microbiological control.

Previous reports of cases of melioidosis that were seen in nonendemic areas of Australia describe recrudescences of latent infection. We describe the case of a patient who presented in the cooler climate of Melbourne with a probable primary, subacute pulmonary infection with Pseudomonas pseudomallei. This case illustrates several points that bear consideration in the management of atypical pneumonia and, more specifically, pulmonary melioidosis. Historical and occupational clues are easily missed or unrecognized, while a persistent growth of gentamicin-resistant Pseudomonas species should arouse suspicion. Septicaemic melioidosis carries a poor prognosis, and treatment should be early and aggressive; use of the newer, third-generation cephalosporin agents should be considered. Given active support in a well-equipped intensive care unit, together with appropriate antibiotic therapy, patients may eventually be cured of this infection, but a high mortality rate is still encountered.

Sera from 9,047 individuals from Northern Queensland were examined for the presence of hemagglutinating antibodies to Pseudomonas pseudomallei, the causative agent of melioidosis, and 512 (5.7%) were found to have titers of 1:40 or greater. The distribution of positive reactors in various groups was uneven, and significantly higher prevalences of positive antibody titers were found in the sera from Aborigines (7.9-10.6%), Torres Strait Islanders (7.8%), Vietnamese refugees (29%) and from persons with certain medical conditions including chronic alcoholism (15%), chronic infections (14.8%), diabetes mellitus (8.6%) and liver disease (12.9%). There were significantly fewer positive reactors (1.4%) amongst the armed forces stationed in Northern Queensland. At present, the boundaries of the major endemic region of Australia extend north from Rockhampton along the coast to Darwin and inland, west from Rockhampton to Tennant Creek in central Australia. Townsville was found to have the highest prevalence (5.2%) of positive reactors of all urban populations of Northern Queensland. The extent of the disease is such that it can no longer be considered a rare infection in Northern Queensland.

Thirteen cases of granuloma inguinale were diagnosed in just over a twelve-month period at the Australian Government Health Laboratory and the General Hospital, Townsville. Seven patients were males, four of whom were immates of Her Majesty's Prison, Townsville. Two of the patients were married, and two were sisters. All the female patients were pregnant at the time of diagnosis. The provisional diagnosis was confirmed by the presence of intracytoplasmic Donovan bodies in crushed tissue smears stained with Wright's stain and pinacyanole. The diagnosis of granuloma inguinale could not be reliably made from sections of formalin-fixed tissue alone. The clinical findings, methods of laboratory diagnosis, management and treatment of this disease are also described with an added emphasis on treatment during pregnancy.

Thirty-six hospitalized patients with circulating antibody to pseudomonas pseudomallei were classified as having either clinical or subclinical melioidosis after full clinical examinations and supplementary radiological and culture investigations. Qualitative estimations of immunoglobulin M (IgM) antibody response were determined by complement fixation, indirect hemagglutination, and immunofluorescence, and the estimations were correlated with the clinical findings in each patient. An attempt was made to appraise the importance of IgM antibody, as determined by each test, in establishing the diagnosis of clinical melioidosis. Results obtained from serological tests were of no value in differentiating between active and latent infections. However, the IgM-immunofluorescent test appeared to be relevant to the diagnosis of clinical melioidosis, since the presence and absence of IgM-immunofluorescent antibody bore a close relation to clinical and subclinical disease, respectively. Surveillance studies indicated that the IgM-immunofluorescent test may be of value in monitoring the activity and treatment of the infection, since the results of the test were generally negative 3 to 6 months after administration of chemotherapy appropriate for melioidosis.

A selective medium consisting of trypticase soy agar with 4% glycerol, 5 mg/l crystal violet, 50 mg/l neutral red and 4 mg/l of gentamicin was devised for isolation of Pseudomonas pseudomallei from clinical specimens. Absorption of neutral red was found to be suitable for differentiating this organism from other bacteria, while gentamicin was effective in selecting Ps. pseudomallei from organisms commonly found in clinical material. The medium was more suitable for screening clinical specimens than MacConkey's agar with colistin-S because it was more selective and allowed multiple specimens to be inoculated on a single plate. Eight thousand clinical specimens from an area endemic for melioidosis were screened on the selective medium. This resulted in the recovery of 8 isolates of Ps. pseudomallei that would not have been detected using routine culture media alone.

Ninety-one strains of Pseudomonas pseudomallei were tested in the API 20E system and in equivalent conventional tests. Except for utilisation of citrate there was good correlation between API and conventional tests. Seven-digit profiles were constructed from each strain after 48 hours' incubation, and numerical codes 2 006 727, 2 206 706, 2 206 707, and 2 206 727 accounted for 77% of strains tested. API 20 E, in combination with tests for heat stability of alkaline phosphatase, resistance to colistin and gentamicin, oxidative attack only of glucose, and acid from maltose, was found to provide a simple method for positive identification of all strains of this organism in two days.

A case of neonatal osteomyelitis and meningitis caused by group B streptococci is reported; the organism isolated was found to be similar or the same as an organism cultured form the maternal vagina. The clinical course and management is also described.

A rapid, reliable immunofluorescent assay for human antibodies to Pseudomonas pseudomallei was devised. The method was found to be sensitive and specific by inhibition tests and by tests for cross reactivity with antisera and cells of closely related pseudomonads other than Pseudomonas mallei. Preliminary studies suggest that the technique may be useful as a screening test for the detection of melioidosis and that demonstration of specific IgM by immunofluorescence may be of value in differentiating active from inactive infection.

Imipenem was highly active and bactericidal against all 100 strains of Pseudomonas pseudomallei tested, followed in activity by piperacillin, carumonam, ceftazidime, cefotaxime, and ceftriaxone. The addition of clavulanic acid significantly increased the activities of both amoxicillin and ticarcillin. Ciprofloxacin and norfloxacin showed poor activity against test strains.

Pseudomonas pseudomallei was recovered from urine specimens of two patients who acquired the organism after they were admitted to a hospital in a region in which it is endemic. Both patients were diabetic and both had urethral catheters passed while they were hospitalized. samples of soil taken from the hospital grounds yielded an isolate of P. pseudomallei that was identical biochemically and by antibiogram to the two isolates recovered from the urine specimens of the two patients. The two patients stayed in wards located in separate hospital blocks, which were geographically distinct but connected by a walkway. The relevant clinical histories of the two patients and the epidemiologic and microbiologic characteristics of the P. pseudomallei isolates were studied. Sera from both patients showed a significant rise in titers of antibody specific for P. pseudomallei. These two patients are considered to represent the first reported cases of hospital-acquired infection due to P. pseudomallei.

During the last 4 years, 20 cases of clinical melioidosis were diagnosed in the geographical area between Tully and Thursday Island. Sixteen were diagnosed by culture of Pseudomonas pseudomallei, and four by positive serology with appropriate clinical features. Most cases occurred during or after a heavy wet season. All patients were adult, and males predominated. Farmers and stockmen represented predisposed populations due to their prolonged soil contact. Ten patients were white Australians, six were Aborigines and four were Torres Strait Islanders. Twelve cases were first diagnosed by positive blood culture and four by sputum culture. The primary site of infection was pulmonary in 14 cases, genitourinary tract in one case, subcutaneous tissues in one case, and joints in two cases. In cases of fulminating infection metastatic abscesses were commonly found in many organs; typically lungs, liver, kidneys and spleen. Six patients had acute fulminating disease and died. Fourteen patients successfully responded to appropriate therapy, but relapse occurred in three, all of whom had an alcohol problem and showed poor drug compliance. The presence of diabetes mellitus in six patients confirmed the important known association of these two diseases. In three fulminating and four subacute infections the serology was negative at the time of diagnosis by culture. Antibiotic therapy for the different forms of this disease is reviewed, and a laboratory protocol for the rapid reporting of positive culture results is included.

An enzyme-linked immunosorbent assay (ELISA) for the detection of specific IgG and IgM antibody to Pseudomonas pseudomallei was developed. The IgG-ELISA was compared with the indirect fluorescence assay for IgG antibody (IgG-IFA) and the indirect hemagglutination (IHA) test in studies with serum specimens from persons from endemic areas for melioidosis and from persons from nonendemic areas of Australia. The sensitivity and specificity of the IgG-ELISA were 90% and 99%, respectively, comparable to those obtained with the IgG-IFA. The IgG-ELISA was more sensitive than the IHA test (74%) and was more suitable than the IgG-IFA as a serologic screening test for melioidosis. The IgM-ELISA was compared with the IgM-IFA as a marker of disease stage in patients with melioidosis. There was good diagnostic agreement between the tests; 92% of patients with active disease gave IgM-ELISA titers greater than or equal to 1:5,120 and 93% of patients with subclinical melioidosis had IgM-ELISA titers less than or equal to 1:1,280. Of the overlap group of patients with a borderline IgM-ELISA titer of 1:2,560, approximately 33% were clinical cases. An uncommon disease stage consisting of a self-limited, short-term, flu-like, pyrexial illness accompanied by elevated serum IgM-ELISA titers (greater than or equal to 1:5,120) was seen in a small number of patients residing in endemic Australia.