Differential patterns of allelic loss in estrogen receptor-positive infiltrating lobular and ductal breast cancer.

The two main histological types of infiltrating breast cancer, lobular (ILC) and the more common ductal (IDC) carcinoma are morphologically and clinically distinct. To assess the molecular alterations associated with these breast cancer subtypes, we conducted a whole-genome study of 166 archival estrogen receptor (ER)-positive tumors (89 IDC and 77 ILC) using the Affymetrix GeneChip(R) Mapping 10K Array to identify sites of loss of heterozygosity (LOH) that either distinguished, or were shared by, the two phenotypes. We found single nucleotide polymorphisms (SNPs) of high-frequency LOH (>50%) common to both ILC and IDC tumors predominately in 11q, 16q, and 17p. Overall, IDC had a slightly higher frequency of LOH events across the genome than ILC (fractional allelic loss = 0.186 and 0.156). By comparing the average frequency of LOH by chromosomal arm, we found IDC tumors with significantly (P < 0.05) higher frequency of LOH on 3p, 5q, 8p, 9p, 20p, and 20q than ILC tumors. We identified additional chromosomal arms differentiating the subtypes when tumors were stratified by tumor size, mitotic rate, or DNA content. Of 5,754 informative SNPs (>25% informativity), we identified 78 and 466 individual SNPs with a higher frequency of LOH (P < 0.05) in ILC and IDC tumors, respectively. Hierarchical clustering of these 544 SNPs grouped tumors into four major groups based on their patterns of LOH and retention of heterozygosity. LOH in chromosomal arms 8p and 5q was common in higher grade IDC tumors, whereas ILC and low-grade IDC grouped together by virtue of LOH in 16q.

Successful control of Scedosporium prolificans septic arthritis and probable osteomyelitis without radical surgery in a long-term renal transplant recipient.

Scedosporium species are increasingly isolated from immunocompromised and immunocompetent patients. Scedosporium infections are generally resistant to multiple antifungals, and Scedosporium prolificans is particularly resistant to all single antifungal agents currently in use with in vitro testing. We report here a long-term renal transplant recipient who developed isolated S. prolificans septic monoarthritis and probable osteomyelitis. The infection was successfully treated with a combination of voriconazole and terbinafine in addition to joint washout but did not require radical surgery. This combination has been shown to have synergistic in vitro effect, and anecdotal in vivo success has also been reported recently. We also review the clinical presentation, treatment, and outcome of S. prolificans infection in patients with solid organ transplantation.

Second intermediate host land snails and definitive host animals of Brachylaima cribbi in southern Australia.

This study of infection of southern Australian land snails with Brachylaima cribbi metacercariae has shown that all commonly encountered native and introduced snails are susceptible second intermediate hosts. The range of infected snails is extensive with metacercariae-infected snails being present in all districts across southern Australia. C. virgata has the highest average natural metacercarial infection intensity of 6.1 metacercariae per infected snail. The susceptibility of birds, mammals and reptiles to B. cribbi infection was studied in South Australia by capturing, dissecting and examining the intestinal tract contents of animals which commonly eat land snails as a food source. Indigenous Australian little ravens (Corvus mellori), which are a common scavenger bird, and two other passeriform birds, the black bird (Turdus merula) and the starling (Sturnus vulgaris), which are both introduced European birds, were found to have the highest infection rates of all animals examined. Other birds found infected with B. cribbi were an emu (Dromaius novaehollandiae), chickens (Gallus gallus) and a pigeon (Columba livia). Natural infections were also detected in field mice (Mus domesticus) and shingleback lizards (Tiliqua rugosa) although the intensity of infection was lower than that observed in birds. Susceptibility studies of laboratory mice, rats and ducks showed that mice developed patent infections which persisted for several weeks, rats developed a short-lived infection of three weeks' duration and ducks did not support infection. This study has shown for the first time that a brachylaimid can infect a wide host range of birds, mammals and reptiles in nature.

Field prevalence and laboratory susceptibility of southern Australian land snails to Brachylaima cribbi sporocyst infection.

Brachylaima cribbi is a terrestrial trematode of birds and mammals with helicid and hygromiid land snails reported as first and second intermediate hosts. However, reports describing the first intermediate host range of B. cribbi have been limited to those snail species present in a small number of geographical locations in South Australia. The natural first intermediate host range, distribution and prevalence of B. cribbi in land snails in southern Australia were determined. A total of 6,432 introduced and native land snails were collected from eight geographical districts across 3,000 km of southern Australia and examined microscopically for B. cribbi sporocysts. Four introduced European snails, Theba pisana, Cernuella virgata, Cochlicella acuta and Cochlicella barbara were natural first intermediate hosts. Sporocyst-infected snails were detected in all districts from Victoria to the west coast of South Australia, a distance of over 1,300 km. Natural sporocyst infection was not observed in introduced European snails Microxeromagna armillata and Helix aspersa or in native Australian land snails Succinea australis and Strangesta gawleri. Egg feeding experiments in the laboratory with B. cribbi confirmed the susceptibility of those species of snails found to be natural first intermediate hosts. Of those species not found to be infected in nature, only M. armillata could be infected in the laboratory. Although this study has shown that five different species of European land snails are suitable first intermediate hosts for B. cribbi there are as yet no reports of B. cribbi from these snails in Europe or from other countries where they have been introduced. Further investigations are needed in Europe to clarify the origins of this parasite.

An outbreak of Legionella longbeachae infection in an intensive care unit?

During a nine-day period, five patients in a 14-bed intensive care unit (ICU) were shown to have seroconverted with a four-fold or greater rise in serum antibody titre to Legionella longbeachae serogroup 1. A further two patients were observed to have high titres consistent with previous exposure but earlier serum samples were not available for comparison. No patients had antibody responses to Legionella pneumophila serogroups 1 and 2. L. longbeachae was not cultured from respiratory secretions from patients or from the environment within the unit. Legionella anisa was recovered from one cooling tower on the ninth floor of the tower block. The ICU is located on the first floor of the same tower and receives external air from two vents, one on the eastern and the other on the western aspect. All patients with serological evidence of L. longbeachae infection were concomitantly infected with multiresistant Staphylococcus aureus, and were located in bays on the eastern side of the unit. A large pigeon nest was discovered within 1-2 m of the eastern vent. Following removal of the birds' nest, no further cases were seen on routine screening of all patients within the unit over the next eight weeks. Alternatively, seroconversion may have been related to demolition of the adjacent nine-storey nurses home. This was begun one month before the first case was diagnosed and was completed four months later. The periodic northerly winds could have carried legionellae from the demolition site directly over the block housing the ICU and may have concentrated them near the eastern air vent. All patients had pneumonia, which was probably multifactorial in origin. There is some uncertainty whether the serological responses seen were an epiphenomenon or were truly indicative of infection with L. longbeachae.

Brachylaima cribbi (Digenea: Brachylaimidae): scanning electron microscopical observations of the life-cycle stages.

Brachylaima cribbi is a recently described species of terrestrial trematode that infects mammals and birds with helicid land snails as its first and second intermediate hosts. The adult worm is 2.5-6.0 mm long by 0.5-0.8 mm wide being a long slender cylindrical worm with oral and ventral suckers in the anterior quarter and genital pore in the posterior quarter. Scanning electron microscopy shows that there is a dense covering of tegumental spines at the anterior end which diminishes towards the posterior extremities of the worm. Development of spines was observed in juvenile and mature adult worms. In young worms 1-3 weeks post infection (wpi) spines appear as buds with a serrated edge each having 1-4 spikes per spine. As the worm ages the spines broaden and by 5 wpi the number of spikes per spine increases to an average of 8.1. The serial development of oral sucker papillae in the cercaria, metacercaria and adult worm was observed with the finding of an elongated papilla with a bifurcated tip on the cercaria becoming a shorter and thicker elongated papilla with a large central stoma on the metacercaria. In the adult worm, this papilla becomes dome-shaped with a small central stoma. For some of these papillae a cilium could be seen extended from the central stoma. Other life-cycle stages illustrated were the hatched egg with an extruded egg membrane minus an operculum and a portion of the branched sporocyst dissected from the digestive gland of the land snail Theba pisana showing a terminal birth pore. Scanning electron microscopy morphological features of the adult worm observed for the first time in a Brachylaima were the unarmed cirrus extended from the genital pore with released sperm present and the Laurer's canal opening visible in tegumental folds on the dorsal surface approximately 300 microm posterior to the genital pore.

Isolation of Helicobacter pylori after transport from a regional laboratory of gastric biopsy specimens in saline, Portagerm pylori or cultured on chocolate agar.

Multiple gastric biopsies were taken from 288 patients in Port Lincoln, South Australia. One biopsy was used for a CLOtest and the other three were transported to a central laboratory in Adelaide in physiological saline, Portagerm pylori transport medium or after culture on a chocolate agar plate which was placed in a Biobag. Helicobacter pylori was isolated from 18.3% of patients. There was a 95.7% concordance between culture results and the CLOtest result. Recovery rates after transport on chocolate agar, Portagerm pylori and in saline were 90.2, 90.2 and 84.3%, respectively.

Description of the life-cycle stages of Brachylaima cribbi n. sp. (Digenea: Brachylaimidae) derived from eggs recovered from human faeces in Australia.

The life-cycle of Brachylaima cribbi n. sp. was established in the laboratory. Asymmetrical brachylaimid eggs, measuring 26-32 microm (29.1 microm) long and 16 -17.5 microm (16.6 microm) wide, were recovered from human faeces and fed to the helicid land snail Theba pisana as the first intermediate host. Sporocysts and cercariae were recovered from the T. pisana eight weeks after infection. The cercariae were used to infect the helicid land snails Cernuella virgata and Helix aspersa as second intermediate hosts. Metacercariae were recovered from the kidneys of these snails and used to infect mice. Adults of Brachylaima cribbi n. sp. were recovered from the small intestine of the mice. The differential features of B. cribbi n. sp. are the specificity for helicid snails as first and second intermediate hosts; characteristic ventral sucker and body cercarial chaetotaxy; and a long slender adult worm with equal size suckers in the first quarter of the worm, the ventral sucker occupying 41% of the body width, the uterus extending anterior to the ventral sucker and the vitelline follicles falling short of the posterior margin of the ventral sucker. No other known Brachylaima species exhibits all of these features. B. cribbi n. sp. is the first brachylaimid known to have infected humans and is probably of European origin, as the intermediate host snails were all introduced into Australia from Europe.

Efficacy of long-term antibiotic suppressive therapy in proven or suspected infected abdominal aortic grafts.

We have reviewed our experience of long-term antibiotic suppressive therapy in patients who underwent repair of an abdominal aortic aneurysm (AAA) and developed proven or strongly suspected infection of a graft. Five patients with abdominal aortic repair complicated by proven or suspected graft infections were treated with continuing antibiotic suppressive therapy based on microbiology culture reports. Two patients developed infection of an established graft, two patients had a graft inserted into an infected area and one patient was thought to be at high risk of developing infection of a recently placed graft. All patients had severe co-existent medical problems and were considered too ill to tolerate further definitive surgery. Response to therapy was monitored by absence of symptoms, fever, inflammatory markers and survival. All patients are alive with a median survival of 32 months, the longest having survived for 6 years. In selected patients with abdominal aortic graft infections, indefinite antibiotic suppressive therapy may be an acceptable alternative to further surgery.

Evaluation of bacteriological transport swabs.

Ten commercial transport swabs were evaluated for their ability to preserve bacteria for 24 and 48 hours. Microorganisms included ATCC strains of Gram-positive and Gram-negative aerobes and anaerobes. There was a wide variation in performance. Swabs using Amies plus charcoal medium or Stuart's medium had better recovery rates than those using Amies medium alone. The nature of the tips of the swabs had little influence. Performance was not correlated with cost of the swabs. These data will assist institutions to make cost-effective decisions when purchasing bacteriological transport systems.

Comparison of culture, histopathology and urease testing for the diagnosis of Helicobacter pylori gastritis and susceptibility to amoxycillin, clarithromycin, metronidazole and tetracycline.

Gastric biopsy specimens were taken from 737 patients undergoing upper gastrointestinal endoscopy and assessed for Helicobacter pylori infection. The diagnostic utilities of H. pylori culture (733 patients), detection of urease production (724 patients) and histopathological examination (469 patients) were compared. Since each of these techniques may fail to diagnose patients infected with H. pylori, an attempt was made to estimate the true rate of infection using a mathematical approach that combined the results of culture, histopathology and urease testing; 34% of the 733 patients were thought to be infected. Using this figure as a benchmark, the sensitivity, specificity, positive predictive value and negative predictive value of H. pylori culture were 73.2%, 100%, 100% and 86.3%, respectively, compared with 58.7%, 100%, 100% and 89.6%, respectively for urease production and 77.0%, 100%, 100% and 82.4%, respectively for histopathology. Thus, histopathological examination was the single most reliable test. A combination of histopathological examination and H. pylori culture diagnosed 99.5% of patients that were estimated to be truly infected. The minimum inhibitory concentrations of a number of antibiotics were measured for 135 isolates of H. pylori. All isolates were susceptible to amoxycillin and tetracycline whereas 5.2% were resistant to clarithromycin and 60% were resistant to metronidazole.

First report of the isolation of an adult worm of the genus Brachylaima (Digenea: Brachylaimidae), from the gastrointestinal tract of a human.

A 78-year-old woman presented with an 18-month history of intermittent diarrhoea. Examination of her stools revealed brachylaimid eggs, which were present in three separate specimens over a week. After treatment with praziquantel a degenerate adult Brachylaima species was recovered from her faeces. She lived in a rural area of South Australia and ate vegetables grown in her own garden which had been infested with helicid snails. In south Australia these introduced European helicid snails are commonly infected with brachylaimid intermediate larval stages and are considered to be the source of the human infection.

Delay in appropriate therapy of Legionella pneumonia associated with increased mortality.

The prognostic significance of delayed therapy in Legionnaires' disease is poorly defined. Thirty-nine consecutive serologically confirmed cases of Legionnaires' disease were reviewed to examine whether an association exists between delayed therapy and prognosis. Clinical and laboratory factors predictive of mortality were also sought. Thirty-one cases (79%) were classified as having severe pneumonia at diagnosis. Thirty-six patients (92%) had community-acquired infection, and three patients (8%) had nosocomial disease. Ten patients died, resulting in a crude mortality rate of 26%. At the first assessment, variables noted for pneumonia associated with death were low diastolic blood pressure (p < 0.02), low serum albumin concentration (p < 0.04), and increased number of days from onset of pneumonia to hospitalisation (prodrome) (p < 0.02). However, multiple logistic regression analysis revealed that the prodrome was the only variable noted at diagnosis that achieved significance (p = 0.024). Mortality also correlated with both delay in the initiation of erythromycin therapy following admission (p < 0.001) and the total delay in starting erythromycin therapy (p < 0.001). It is therefore recommended that erythromycin be included early in the empiric therapy of severe community-acquired pneumonia.

Comparison of direct and standardized testing of infected urine for antimicrobial susceptibilities by disk diffusion.

A total of 14,272 urine specimens were examined over one year to determine the validity of direct antimicrobial agent susceptibility testing against ampicillin, amoxicillin-clavulanic acid, cephalothin, gentamicin, norfloxacin, and trimethoprim. A comparison between direct and standardized disk diffusion tests was made for a total of 1,106 urine specimens containing > or = 10(5) organisms per ml in pure culture. There were 5,821 individual organism-antimicrobial agent challenges compared for the two testing methods, and there was complete agreement of susceptibility category in 5,492 comparisons (94.3%). Initially, discordant results were reduced from 5.7 to 2.1% when the intermediate category was considered susceptible. Intralaboratory variation was assessed by testing another 453 organisms by the standard National Committee for Clinical Laboratory Standards (NCCLS) method on two consecutive days; there was complete agreement in 96.1% of comparisons. When results of direct and standardized testing were simply classified as susceptible or resistant, there was 1.1% discordance. When simple same-day tests were used together with predictable patterns of susceptibility and resistance, 536 (48.5%) of 1,106 isolates could be identified satisfactorily to the genus or species level. For laboratory reporting purposes, the direct method is equivalent to the standard method when the urine being tested is infected with > or = 10(5) organisms of a single type per ml. The presence or absence of preexisting antimicrobial agents in urine did not appreciably influence the results. This procedure allows the earlier reporting of susceptibility results and facilitates less expensive identification of many organisms. Costs and benefits need to be determined in each institution.

Worms in Australia.

Fortunately, Australia does not have many of the parasitic worm infections, such as filariasis, onchocerciasis and dracunculiasis, that are important on a global scale. Nevertheless, several medically important parasitic worms are endemic in Australia. Intestinal nematodes occur mostly in the tropical north although threadworm is ubiquitous. Hydatid disease and tapeworm infections occur especially in sheep and cattle farming regions.

Analysis of the 18S ribosomal RNA gene of Strongyloides stercoralis.

The entire 1766 bases of the 18S rRNA gene of Strongyloides stercoralis have been sequenced. The gene has a 38% G+C content. Although it is similar in length to the 18S rRNA gene of Caenorhabditis elegans, the only other completely sequenced nematode 18S rRNA gene, it is only 69% identical. Closely related helminths will need to be sequenced in order to delineate sequences specific for the diagnosis of strongyloidiasis.

Corneal ulceration due to Nocardia asteroides.

A case of corneal ulceration due to infection with Nocardia asteroides is described. Microbiological examination of corneal scrapings permitted accurate diagnosis and suggested appropriate therapy. Nineteen other cases that have been described in the world literature are reviewed.

Strongyloides stercoralis: antigenic analysis of infective larvae and adult worms.

The protein composition of Strongyloides stercoralis infective larvae and adult worms solubilized sequentially in water, sodium deoxycholate and sodium dodecyl sulphate (SDS) and their excretory/secretory products were analysed by one- and two-dimensional SDS-polyacrylamide electrophoresis. These extracts were demonstrated to be complex mixtures containing many proteins, some of which were common and others which were stage-specific. Western blot analysis of these antigens with infected human sera showed most sero-reactivity against larval antigens, whilst normal human sera were unreactive. These data identify immunogenic antigens which may be available for detection in an antigen assay.