A case of disseminated cryptococcosis with abdominal involvement due to Cryptococcus neoformans species complex in a Ragdoll cat and false-negative cryptococcal antigen lateral flow tests due to the postzone phenomenon

Although cryptococcosis is the most common systemic fungal disease of cats, abdominal involvement is rarely reported. The pathogenesis of cryptococcosis usually involves sinonasal colonisation, followed by tissue invasion and sinonasal infection, with possible subsequent spread to the lungs and/or direct extension into the central nervous system (CNS), for example, via the cribriform plate. Further haematogenous spread can occur to any tissue, including skin and the CNS. This report describes a case of disseminated cryptococcosis due to Cryptococcus neoformans species complex in a 13-year-old cat, the fourth documented Australian feline case with abdominal involvement. The cat presented with a chronic history of upper respiratory disease that progressed to severe lethargy and anorexia. An autopsy revealed striking peritonitis with multifocal abdominal involvement affecting the liver, spleen, adrenal glands, kidneys, pancreas and mesentery. Cryptococcal organisms were also observed in organs within the thoracic cavity, sinonasal tissues and the CNS. Testing of abdominal fluid and serum for cryptococcal antigen using a commercially available lateral flow assay using neat fluid specimen initially tested false-negative. However, after dilution of the sample to 1:64, a positive result was obtained, confirming a postzone phenomenon. Taken together, the collective findings were indicative of widely disseminated cryptococcosis due to Cryptococcus neoformans with atypical involvement of the abdominal cavity.

Abdominal cryptococcosis in dogs and cats: 38 cases (2000-2018)

INTRODUCTION

To report the clinical presentation, laboratory and imaging findings, treatment and outcome of abdominal cryptococcosis in dogs and cats in Australia.

MATERIALS AND METHODS

Canine and feline cases from Australia were retrospectively identified (2000 to 2018) via laboratory and referral centre searches for abdominal cryptococcosis diagnosed by cytology (needle aspirates) or histopathology (biopsy or necropsy) of abdominal organs/tissues. Signalment, presenting complaints, clinical signs, laboratory findings, medical imaging, latex cryptococcal antigen agglutination test (LCAT) titres, treatment and outcome data was collected.

RESULTS

Thirty-eight cases were included (35 dogs, three cats) in the study. Median age of presentation was 2 years for dogs and 6 years for cats. Common presenting complaints included vomiting (23/38), lethargy (19/38) and inappetence/anorexia (15/38). Abdominal ultrasound (25/38 cases) revealed mesenteric and intestinal lesions in most of the cases. On surgical exploration, seven cases had an intestinal lesion associated with an intussusception. Nineteen cases had a pre-treatment LCAT performed, with a median initial titre of 1:2048 (range 1:2 to 65,536). Twenty-four cases (23 dogs, one cat) received treatment, either medical, surgical or both. Median survival time for cases with combined medical and surgical treatment, surgical treatment alone or medical treatment alone was 730, 140 and 561 days, respectively. Eleven remain alive at the time of follow up.

CLINICAL SIGNIFICANCE

Abdominal cryptococcosis although rare should be a considered as a diagnostic possibility in an especially young dog presenting with gastro-intestinal signs. Older dogs can also present with this condition and should not be euthanised based on imaging alone due to the likenesses with neoplasia. With appropriate treatment and monitoring many dogs may have a prolonged survival period and some may be cured.

Immunohistochemical Analysis of Leucocyte Subsets in the Sinonasal Mucosa of Cats with Upper Respiratory Tract Aspergillosis

Leucocyte populations in the sinonasal mucosa of cats with and without upper respiratory tract aspergillosis were compared using immunohistochemistry and computer-aided morphometry. Inflammation was identified in the nasal mucosa of all affected cats, comprising predominantly of lymphoplasmacytic infiltration of the lamina propria associated with epithelial proliferation and degeneration. There was intense and diffuse expression of class II antigens of the major histocompatibility complex, associated with sites of hyphal invasion with hyperplasia and ulceration of the epithelium adjacent to fungal elements. Significantly more CD79b(+) cells, total lymphocytes, immunoglobulin (Ig)-expressing cells and MAC387(+) cells infiltrated the epithelium and more IgG(+) cells and total Ig-expressing cells infiltrated the lamina propria in affected cats compared with controls. Importantly, the inflammatory profile in affected cats was not consistent with the T helper (Th)1 and Th17 cell-mediated response that confers protective acquired immunity against invasive aspergillosis in dogs and people and in murine models of the infection. This finding may help to explain the development of invasive aspergillosis in systemically immunocompetent cats.

Gynäkologische Malignome bei Patientinnen mit rheumatisch‑entzündlichen Systemerkrankungen

Das Risiko für gynäkologische Tumoren bei rheumatisch-entzündlichen Systemerkrankungen scheint nur in Bezug auf das Zervixkarzinom v. a. bei systemischem Lupus erythematodes erhöht zu sein. Studien weisen auf die Bedeutung des Immunsystems für die Tumorkontrolle bei gynäkologischen Tumoren hin. Bislang konnte aber nur für das Zervixkarzinom ein ungünstiger Einfluss einer medikamentösen Immunsuppression bei rheumatologischen Patientinnen gezeigt werden. Biologika wirken sich bei dieser Entität dagegen nicht eindeutig tumorfördernd aus. Die Datenlage bei dieser Fragestellung ist allerdings begrenzt. Generelle Screeningempfehlungen existieren für das Mammakarzinom und das Zervixkarzinom. Empfehlungen zur Tumornachsorge werden dargestellt. Aufgrund der unzureichenden Datenlage empfiehlt sich zumindest in den ersten 5 Jahren nach kurativer onkologischer Therapie eine sehr strenge Indikationsstellung zum Einsatz von Immunsuppressiva und Biologika auch bei gynäkologischen Tumoren. Im Falle des Mammakarzinoms wird sogar die Beachtung eines längeren Intervalls diskutiert.

Some pharmacokinetic indices of oral fluconazole administration to koalas (Phascolarctos cinereus) infected with cryptococcosis

Three asymptomatic koalas serologically positive for cryptococcosis and two symptomatic koalas were treated with 10 mg/kg fluconazole orally, twice daily for at least 2 weeks. The median plasma Cmax and AUC0-8 h for asymptomatic animals were 0.9 μg/mL and 4.9 μg/mL·h, respectively; and for symptomatic animals 3.2 μg/mL and 17.3 μg/mL·h, respectively. An additional symptomatic koala was treated with fluconazole (10 mg/kg twice daily) and a subcutaneous amphotericin B infusion twice weekly. After 2 weeks the fluconazole Cmax was 3.7 μg/mL and the AUC0-8 h was 25.8 μg/mL*h. An additional three koalas were treated with fluconazole 15 mg/kg twice daily for at least 2 weeks, with the same subcutaneous amphotericin protocol co-administered to two of these koalas (Cmax : 5.0 μg/mL; mean AUC0-8 h : 18.1 μg/mL*h). For all koalas, the fluconazole plasma Cmax failed to reach the MIC90 (16 μg/mL) to inhibit C. gattii. Fluconazole administered orally at either 10 or 15 mg/kg twice daily in conjunction with amphotericin is unlikely to attain therapeutic plasma concentrations. Suggestions to improve treatment of systemic cryptococcosis include testing pathogen susceptibility to fluconazole, monitoring plasma fluconazole concentrations, and administration of 20-25 mg/kg fluconazole orally, twice daily, with an amphotericin subcutaneous infusion twice weekly.

In vitro hepatic microsomal metabolism of meloxicam in koalas (Phascolarctos cinereus), brushtail possums (Trichosurus vulpecula), ringtail possums (Pseudocheirus peregrinus), rats (Rattus norvegicus) and dogs (Canis lupus familiaris)

Quantitative and qualitative aspects of in vitro metabolism of the non-steroidal anti-inflammatory drug meloxicam, mediated via hepatic microsomes of specialized foliage (Eucalyptus) eating marsupials (koalas and ringtail possums), a generalized foliage eating marsupial (brushtail possum), rats, and dogs, are described. Using a substrate depletion method, intrinsic hepatic clearance (in vitro Clint) was determined. Significantly, rates of oxidative transformation of meloxicam, likely mediated via cytochromes P450 (CYP), were higher in marsupials compared to rats or dogs. The rank order of apparent in vitro Clint was brushtail possums (n=3) (mean: 394μL/min/mg protein), >koalas (n=6) (50), >ringtail possums (n=2) (36) (with no significant difference between koalas and ringtail possums), >pooled rats (3.2)>pooled dogs (in which the rate of depletion, as calculated by the ratio of the substrate remaining was <20% and too slow to determine). During the depletion of meloxicam, at a first-order rate constant, 5-hydroxymethyl metabolite (M1) was identified in the brushtail possums and the rat as the major metabolite. However, multiple hydroxyl metabolites were observed in the koala (M1, M2, and M3) and the ringtail possum (M1 and M3) indicating that these specialized foliage-eating marsupials have diverse oxidation capacity to metabolize meloxicam. Using a well-stirred model, the apparent in vitro Clint of meloxicam for koalas and the rat was further scaled to compare with published in vivo Cl. The closest in vivo Cl prediction from in vitro data of koalas was demonstrated with scaled hepatic Cl(total) (average fold error=1.9) excluding unbound fractions in the blood and microsome values; whereas for rats, the in-vitro scaled hepatic Cl fu(blood, mic), corrected with unbound fractions in the blood and microsome values, provided the best prediction (fold error=1.86). This study indicates that eutherians such as rats or dogs serve as inadequate models for dosage extrapolation of this drug to marsupials due to differences in hepatic turnover rate. Furthermore, as in vivo Cl is one of the pharmacokinetic indexes for determining therapeutic drug dosages, this study demonstrates the utility of in vitro to in vivo scaling as an alternative prediction method of drug Cl in koalas.

Computed tomographic anatomy of the nasal cavity, paranasal sinuses and tympanic cavity of the koala

OBJECTIVE

To use cross-sectional imaging (helical computed tomography (CT)) combined with conventional anatomical dissection to define the normal anatomy of the nasal cavity and bony cavitations of the koala skull.

METHODS

Helical CT scans of the heads of nine adult animals were obtained using a multislice scanner acquiring thin slices reconstructed in the transverse, sagittal and dorsal planes. Subsequent anatomical dissection permitted confirmation of correct identification and further delineation of bony and air-filled structures visible in axial and multiplanar reformatted CT images.

RESULTS

The nasal cavity was relatively simple, with little scrolling of nasal conchae, but bony cavitations were complex and extensive. A rostral maxillary recess and ventral conchal, caudal maxillary, frontal and sphenoidal paranasal sinuses were identified and characterised. Extensive temporal bone cavitation was shown to be related to a large epitympanic recess.

CONCLUSIONS

The detailed anatomical data provided are applicable to future functional and comparative anatomical studies, as well as providing a preliminary atlas for clinical investigation of conditions such as cryptococcal rhinosinusitis, a condition more common in the koala than in many other species.

Pharmacokinetics of chloramphenicol following administration of intravenous and subcutaneous chloramphenicol sodium succinate, and subcutaneous chloramphenicol, to koalas (Phascolarctos cinereus)

Clinically normal koalas (n = 19) received a single dose of intravenous (i.v.) chloramphenicol sodium succinate (SS) (25 mg/kg; n = 6), subcutaneous (s.c.) chloramphenicol SS (60 mg/kg; n = 7) or s.c. chloramphenicol base (60 mg/kg; n = 6). Serial plasma samples were collected over 24-48 h, and chloramphenicol concentrations were determined using a validated high-performance liquid chromatography assay. The median (range) apparent clearance (CL/F) and elimination half-life (t(1/2)) of chloramphenicol after i.v. chloramphenicol SS administration were 0.52 (0.35-0.99) L/h/kg and 1.13 (0.76-1.40) h, respectively. Although the area under the concentration-time curve was comparable for the two s.c. formulations, the absorption rate-limited disposition of chloramphenicol base resulted in a lower median C(max) (2.52; range 0.75-6.80 μg/mL) and longer median tmax (8.00; range 4.00-12.00 h) than chloramphenicol SS (C(max) 20.37, range 13.88-25.15 μg/mL; t(max) 1.25, range 1.00-2.00 h). When these results were compared with susceptibility data for human Chlamydia isolates, the expected efficacy of the current chloramphenicol dosing regimen used in koalas to treat chlamydiosis remains uncertain and at odds with clinical observations.

New erythrocyte and reticulocyte parameters on CELL-DYN Sapphire: analytical and preanalytical aspects

INTRODUCTION

Extended RBC and reticulocyte parameters are useful in diagnosing functional iron deficiency and various other clinical conditions. The newest software of the CELL-DYN Sapphire measures extended RBC and reticulocyte parameters. The aims of the present communication were to assess the analytical aspects of these parameters compared with the Siemens Advia 120 analyzer, to study the effect of sample aging and to briefly explore their clinical usefulness in patients with anemia.

METHODS

Blood samples were obtained from the routine workload of two hospital laboratories and were run on Siemens Advia and Abbott CELL-DYN Sapphire analyzers in parallel. Data analysis was performed using standard statistics.

RESULTS

In total, 1416 patient samples were analyzed. There was close correlation in microcytic and macrocytic RBC (r(2) > 0.97) with small bias. The hypo- and hyperchromic RBC showed reasonable correlations, Advia 120 giving higher values. Reticulocyte MCV showed acceptable agreement, with significant proportional bias (Advia 8-9% higher). CELL-DYN Sapphire MCHr correlated rather well with Advia CHr (r(2) > 0.91) with significant absolute bias. Remarkably, the correlation data differed significantly between the two laboratories. It was found that aging of EDTA samples had significant effect on most of the RBC parameters.

CONCLUSIONS

The new RBC parameters of CELL-DYN Sapphire generally correlated well with those of Advia 120, although significant systematic differences were present, particularly in reticulocyte MCH and MCV. These differences necessitate instrument-specific reference ranges and clinical decision values. To minimize preanalytical effects, these parameters should be measured in fresh blood samples.

Sequential opportunistic infections in two German Shepherd dogs

Two German Shepherd dogs with sequential opportunistic infections are described. The first was a 2-year-old male with cryptococcal rhinitis that spread to involve the optic nerves and brain. It was successfully treated with combination therapy utilising amphotericin B administered for 2 years, but the dog developed a disseminated Aspergillus deflectus infection 5 years later and was euthanased. The second case was a 4-year-old male that presented for a severe, deep-seated infection of the right antebrachium, with gradual extension to contiguous tissues. Neosartorya fischeri (anamorph; Aspergillus fischerianus) was isolated in pure culture and detected in histological sections. The infection was refractory to itraconazole, but resolved after amputation of the affected limb. Five months later, the dog developed a localised cutaneous lesion on the proximal pelvic limb, from which Pythium insidiosum was isolated and then visualised in tissue sections, together with a structure thought to be grass seed. This lesion was treated by wide surgical resection, although it was reported that the dog died of disseminated disease some months later. These cases provide further circumstantial evidence that young adult German Shepherd dogs have a predilection to developing invasive infections with fungi and other saprophytic pathogens.

Whole blood-derived miRNA profiles as potential new tools for ovarian cancer screening

BACKGROUND

Screening is an unsolved problem for ovarian cancer (OvCA). As late detection is equivalent to poor prognosis, we analysed whether OvCA patients show diagnostically meaningful microRNA (miRNA) patterns in blood cells.

METHODS

Blood-borne whole miRNome profiles from 24 patients with OvCA and 15 age- and sex-matched healthy controls were biostatistically evaluated.

RESULTS

Student's t-test revealed 147 significantly deregulated miRNAs before and 4 after Benjamini-Hochberg adjustment. Although these included miRNAs already linked to OvCA (e.g., miR-16, miR-155), others had never before been connected to specific diseases. A bioinformatically calculated miRNA profile allowed for discrimination between blood samples of OvCA patients and healthy controls with an accuracy of >76%. When only cancers of the serous subtype were considered and compared with an extended control group (n=39), accuracy, specificity and sensitivity all increased to >85%.

CONCLUSION

Our proof-of-principle study strengthens the hypothesis that neoplastic diseases generate characteristic miRNA fingerprints in blood cells. Still, the obtained OvCA-associated miRNA pattern is not yet sensitive and specific enough to permit the monitoring of disease progression or even preventive screening. Microarray-based miRNA profiling from peripheral blood could thus be combined with other markers to improve the notoriously difficult but important screening for OvCA.

Expression of transketolase-like 1 protein (TKTL1) in human endometrial cancer

BACKGROUND

Malignant tumors metabolize glucose to lactate even in the presence of oxygen (aerobic glycolysis). The metabolic switch from oxidative glycolysis to non-oxidative fermentation of glucose and proteins performed by the tumor cells seems to be associated with TKTL1 and pAkt overexpression. Therefore the aim of the present study was to investigate the expression of TKTL1 and pAkt in human specimens of endometrial cancer as compared to benign endometrium. Additionally, expression of the glucose transporter GLUT1 was also investigated as aerobic glycolysis is associated with an increased need for glucose.

MATERIALS AND METHODS

Levels of TKTL1, pAkt, and GLUT1 expression were immunhistochemically evaluated on paraffin embedded biopsy material from 10 benign and 41 malignant endometrial tissue samples. TKTL1 mRNA levels in the endometrial cancer cell lines Ishikawa and HEC-1A were evaluated by RT-PCR.

RESULTS

Expression of TKTL1, GLUT1 and pAKT was significantly increased in endometrial carcinomas as compared to benign endometrial tissue. There was a significantly weaker TKTL1 expression in highly differentiated G1 tumors. In the human endometrial cancer cell lines Ishikawa and HEC-1A, TKTL1 mRNA was clearly detectable.

CONCLUSION

The levels of TKTL1, GLUT1 and pAKT expression point to the glycolytic phenotype of malignant endometrial tissue. Given the pronounced TKTL1 expression across all different subtypes of endometrial cancer, this protein could serve as a target for future cancer treatments.

Overexpression of polycomb protein BMI-1 in human specimens of breast, ovarian, endometrial and cervical cancer

INTRODUCTION

The polycomb group (PcG) proteins form chromatin-modifying complexes that are commonly deregulated in cancer. The PcG protein BMI-I is overexpressed by various tumours and thus may contribute to malignant transformation. The current study investigated the expression of BMI-I in human specimens of breast, ovarian, endometrial and cervical cancer.

MATERIALS AND METHODS

Expression of BMI-I was evaluated in human ovarian cancer samples by Western blot analysis and immunohistochemistry (IHC) and compared to healthy ovarian tissue. BMI-I expression in human specimens of breast, endometrial and cervical cancer was evaluated by IHC and then compared with the respective benign tissues.

RESULTS

BMI-I was significantly (p<0.05) overexpressed in human breast, ovarian, endometrial and cervical cancer specimens as compared to benign controls. BMI-I expression was also more pronounced in the ovarian cancer samples as demonstrated by Western blot analysis. In human breast cancer samples, BMI-I expression was most pronounced in the invasion front of the tumour.

CONCLUSION

The current study showed for the first time that the BMI-I protein is significantly overexpressed in ovarian, endometrial and cervical cancer and may thus be a potential target for novel antitumor therapies.

Prolonged clinical benefit from platinum-based chemotherapy in a patient with metastatic triple negative breast cancer

Triple negative breast cancer is a recently defined subgroup of tumors which do not express receptors for estrogen or progesterone and which do not show any overexpression of HER2 receptors. Tumors with these histopathologic features have an unfavorable prognosis and at present there is no standard chemotherapy regimen available. However, experimental studies and very recently some clinical data showed a benefit from platinum-based chemotherapy. We treated a 52-year-old caucasian female with metastatic triple negative breast cancer. She suffered from extensive liver disease resistant to taxane treatment and yttrium radiotherapy. Cisplatin/ifosfamide (12 cycles) induced regression of the liver metastasis from over 30 cm to 6 cm as revealed by CT scan. Dose-limiting toxicity was impairment of renal function and pancytopenia. The patient has now been stable for over ten months on a metronomic regimen of oral cyclophosphamide. This case report adds to recent evidence suggesting good clinical benefits of platinum-based regimens in early and advanced triple negative breast cancers.

Spinal cryptococcoma in an immunocompetent cat

This report describes an unusual case of primary cryptococcoma in the proximal thoracic spinal cord of an 11-year-old immunocompetent cat from a farm on which there were large numbers of pigeons. This animal was referred for examination with progressive paralysis and shown to be free from feline immunodeficiency virus, feline leukaemia virus, feline coronavirus and Toxoplasma gondii. It died 2 months later. At necropsy, the only lesion detected was a malacic area, 4cm in length, in the spinal cord. Histopathological examination of the spinal cord revealed severe granulomatous inflammation associated with large numbers of encapsulated yeast cells. In addition to the granulomatous host response, necrosis, digestion chambers, Gitter cells, spheroids and lymphocytic perivascular cuffs were features of the malacic areas. Immunohistochemistry confirmed the presence of Cryptococcus neoformans var. grubii yeast cells.

Successful treatment of cryptococcal pneumonia in a pony mare

A 20-year-old Welsh Mountain Pony (212 kg) mare was initially presented for a chronic cough, fever, weight loss and low grade abdominal pain. She later developed dyspnoea, tachypnoea and exercise intolerance. The presence of multiple masses (up to 17 cm diameter) in the pulmonary parenchyma was established using lateral thoracic radiography and transthoracic ultrasonography. Encapsulated, budding yeasts were observed in smears made from transtracheal washings and needle aspirates of the pulmonary lesions. Cryptococcus gattii (synonym: Cryptococcus neoformans variety gattii; Cryptococcus bacillisporus) was cultured from the transtracheal washings and aspirates of the lung masses. The pony was successfully treated using daily intravenous infusions of amphotericin B (typically 0.5 mg/kg in 1 L 5% dextrose in water over 1 h, following premedication with 50 mg flunixin intravenously) over a 1 month period, until a cumulative dose of 3 g had been administered. Treatment was considered to be successful on the basis of progressive improvement in clinical signs, reduction in the size of pulmonary cryptococcomas, 48 kg weight gain and a reduction in the cryptococcal antigen titre from 4096 to 256, 1 year after cessation of treatment.

Transketolase-like 1 expression correlates with subtypes of ovarian cancer and the presence of distant metastases

Tumorbiology of ovarian cancer remains unclear. However, it is known that ovarian tumors, especially carcinomas, show elevated expression of glucose membrane transporters for facilitated glucose uptake. It can be assumed that increased glucose uptake leads to higher glucose metabolism. The energy resources of fully malignant transformed carcinomas are mainly supplied by aerobic glycolysis, for which several pathways are known. A key role in aerobic glycolysis is described for the transketolase enzymes. Recently, a novel transketolase-like enzyme called transketolase-like 1 (TKTL1) has been described that links aerobic glycolysis to the synthesis of fatty acids via production of acetyl-CoA. In order to investigate the role of TKTL1 for the progression of ovarian carcinomas, we examined paraffin sections of normal ovarian tissues, ovarian borderline tumors, and mucinous or serous papillary ovarian adenocarcinomas with respect to their expression of TKTL1. We identified a significantly elevated expression of TKTL1 in serous papillary ovarian adenocarcinomas, which correlates with poor prognostic parameters in the examined study group. Therefore, it can be assumed that TKTL1 plays a crucial role in ovarian cancer metabolism and that its expression predicts poor prognosis. Further investigations should be performed in order to evaluate whether this new enzyme is important for ovarian cancer tumorbiology and to analyze the potential role of TKTL1 as new target for specific antitumoral therapy.

Protothecosis in 17 Australian dogs and a review of the canine literature

Systemic protothecosis was diagnosed in 17 Australian dogs between 1988 and 2005. There was a preponderance of young-adult (median 4 years), medium- to large-breed dogs. Females (12/17 cases) and Boxer dogs (7 cases, including 6 purebreds and one Boxer cross) were over-represented. Sixteen of 17 dogs died, with a median survival of four months. A disproportionate number of cases were from coastal Queensland. In most patients, first signs were referable to colitis (11/17 cases), which varied in severity, and was often present for many months before other symptoms developed. Subsequent to dissemination, signs were mostly ocular (12 cases) and/or neurologic (8 cases). Two dogs had signs due to bony lesions. Once dissemination was evident, death or euthanasia transpired quickly. Prototheca organisms had a tropism for the eye, central nervous system (CNS), bone, kidneys and myocardium, tissues with a good blood supply. Microscopic examination and culture of urine (5 cases), cerebrospinal fluid (CSF;1 case), rectal scrapings (4 cases), aspirates or biopsies of eyes (5 cases) and histology of colonic biopsies (6 cases) as well as skin and lymph nodes (2 cases) helped secure a diagnosis. Of the cases where culture was successful, P wickerhamii was isolated from two patients, while P zopfii was isolated from five. P zopfii infections had a more aggressive course. Treatment was not attempted in most cases. Combination therapy with amphotericin B and itraconazole proved effective in two cases, although in one of these treatment should have been for a longer duration. One surviving dog is currently still receiving itraconazole. Protothecosis should be considered in all dogs with refractory colitis, especially in female Boxers.

Long-term outcome of therapy for 59 cats and 11 dogs with cryptococcosis

OBJECTIVE

To determine the outcome of therapy in cats and dogs with naturally occurring cryptococcosis. Design Retrospective study of 59 cats and 11 dogs at the University Veterinary Centre Sydney from 1986 to 2004.

METHOD

Following detailed analysis of case notes potential associations between patient characteristics, cryptococcal species, retroviral status (cats), disease severity and type of therapy were examined in relation to duration and success of therapy. Treatment protocols based on amphotericin B, fluconazole and itraconazole were compared.

RESULTS

Seventy-six percent of feline patients were successfully treated. For cats, the presence of central nervous system disease was the only factor found to influence outcome. Cats with neurological involvement, disseminated disease or refractory disease treated with amphotericin B containing protocols did as well, on average, as cats with less severe disease treated with azole monotherapy. Amphotericin B was thus an effective agent for treating severe cases of cryptococcosis. The median cumulative dose of amphotericin B for cats cured at the first attempt was 16 mg/kg (range 7 to 23 mg/kg). The median duration of treatment required to effect a cure at first attempt was significantly shorter for fluconazole (4 months; range 1 to 8 months) than for itraconazole (9 months; range 3 to 24 months; P = 0. 0191; Mann Whitney U test). The success rate for treatment of canine cases was 55%. No factor appeared to influence disease outcome in dogs. Large cumulative doses of amphotericin B could be administered via the subcutaneous route in both species and generally with minimal nephrotoxicity. Recrudescence occurred in a significant proportion of animals, in some cases despite a reduction of serum latex cryptococcal antigen agglutination test to zero.

CONCLUSION

Although the prognosis of cryptococcosis should be described as guarded, a majority of the canine and especially feline patients can be expected to be cured, although treatment is protracted and expensive.

Increased tartrate-resistant acid phosphatase (TRAP) expression in malignant breast, ovarian and melanoma tissue: an investigational study

Background

Tartrate-resistant acid phosphatase (TRAP) is a metalloprotein enzyme that belongs to the acid phosphatases and is known to be expressed by osteoclasts. It has already been investigated as a marker of bone metastases in cancer patients. In this study, which examined the value of serum TRAP concentrations as a marker of bone disease in breast cancer patients, we observed high concentrations of TRAP even in patients without bone metastases. To elucidate this phenomenon, we examined the expression of TRAP in breast cancer cells and the cells of several other malignancies.

Methods

TRAP concentrations in the serum of tumor patients were determined by ELISA. The expression of TRAP in breast, ovarian, and cervical cancer and malignant melanoma was analyzed by immunohistochemistry. RT-PCR and immunocytology were used to evaluate TRAP expression in cultured tumor cells.

Results

A marked increase in serum TRAP concentrations was observed in patients with breast and ovarian cancer, regardless of the presence or absence of bone disease. TRAP expression was found in breast and ovarian cancers and malignant melanoma, while cervical cancer showed only minimal expression of TRAP. Expression of TRAP was absent in benign tissue or was much less marked than in the corresponding malignant tissue. TRAP expression was also demonstrated in cultured primary cancer cells and in commercially available cell lines.

Conclusion

Overexpression of TRAP was detected in the cells of various different tumors. TRAP might be useful as a marker of progression of malignant disease. It could also be a potential target for future cancer therapies.

Nocardia infections in cats: a retrospective multi-institutional study of 17 cases

OBJECTIVE

To record 17 cases of nocardiosis in cats from eastern Australia and to compare this series with cases previously reported.

DESIGN

Retrospective/prospective study.

RESULTS

Nocardia spp infections were diagnosed in 17 cats over 14 years from the three eastern states of Australia. There were no isolates from dogs during this period, but one isolate from a koala and two from dairy cows. The majority of cats presented with spreading lesions of the subcutis and skin associated with draining sinus tract(s). Early cutaneous lesions consisted of circumscribed abscesses. Infections spread at a variable rate, generally by extension to adjacent tissues. Lesions were generally located in regions subjected to cat bite or scratch injuries, including limbs, body wall, inguinal panniculus and nasal bridge. In some other cases, lesions were situated on distal extremities. The clinical course was variable, from chronic, indolent, initially localised infections to acute fulminating disease. Of the 17 cats, 14 were domestic crossbreds and three were purebreds. There was a preponderance of male cats (12 castrated, 1 entire young adult, 1 entire kitten). Nine of 17 cats were 10 years or older. Interestingly, the majority of infections were attributable to N nova. Immediate and/or predisposing causes could be identified in all cases, and included: renal transplantation [one cat]; chronic corticosteroid administration [three cats]; catabolic state following chylothorax surgery [one cat]; fight injuries [seven cats]; FIV infections [three of seven cats tested]. Of the 17 cats, three were apparently cured. Four were thought to be cured, but infection recurred after several months. Three cats responded partially but were euthanased, while another was improving when it died of unrelated complications. Two died despite treatment and two were euthanased without an attempt at therapy. For two cats there were either insufficient records or the patient was lost to follow up.

CONCLUSION

Nocardiosis is a rare, serious disease. Currently it is more common in cats than dogs. Nocardial panniculitis may be clinically indistinguishable from the syndrome caused by rapidly growing mycobacteria. Although the prognosis is guarded, patients with localised infections caused by N nova often respond to appropriate therapy. If definitive treatment is delayed because of misdiagnosis, the disease tends to become chronic, extensive and refractory. Insufficient duration of therapy leads to disease recurrence.

Recrudescent cryptococcosis, caused byCryptococcus gattii(molecular type VGII),over a 13-year period in a Birman cat

A 17-year-old desexed male Birman cat presented with a fleshy mass protruding from the left ear canal. A culture from the mass revealed a heavy growth of Cryptococcus gattii (molecular type VGII, serotype B). The lesion resolved with antifungal therapy over 8 weeks. Itraconazole was continued indefinitely due to persistent high serum cryptococcal antigen titres. The cat was euthanased 12 months later due to the acute development of hindlimb ataxia and collapse which may or may not have been attributable to cryptococcosis. This cat had first presented when 4 years of age with a 3-week history of inappetance, sneezing and serous nasal discharge. Culture of swabs from both nostrils were positive for C. gattii (VGII). Fluconazole therapy produced steady improvement over a 6 month period, at which time therapy was discontinued. The cat presented 9 months later for sneezing, again with a positive culture of C. gattii from the nasal cavity. Antifungal therapy was continued for 8 months, after which time cultures were negative and symptoms resolved. Three episodes of cryptococcosis in a cat over a 13-year period were thus documented. Importantly, the two C. gattii isolates, obtained 13 years apart, were identical using DNA fingerprinting and random amplification of polymorphic DNA (RAPD) analysis.

Hepatocellular carcinoma with secondary abscessation in a cat

A 16-year-old castrated male domestic shorthair cat was presented for investigation of weight loss, lethargy, inappetence and polydypsia. On serum biochemical analysis there was evidence of severe hepatocellular damage and cholestasis. Abdominal ultrasonographic examination revealed an irregular lesion of mixed echogenicity in a left hepatic lobe. It was compromised of a hypoechoic periphery surrounding an anechoic central area containing highly echogenic densities with distal acoustic shadowing suggestive of gas formation. On necropsy, the only gross abnormality was a solitary 5 cm x 3 cm x 3 cm multilobulated mass in the left lateral hepatic lobe, containing foul-smelling purulent fluid within a thick fibrous wall. Cytological examination of the fluid revealed numerous degenerate neutrophils and large numbers of Gram-positive spore-forming rods. The histopathological diagnosis was hepatocellular carcinoma with secondary abscessation. The bacterial morphology was consistent with Clostridia sp. Both hepatocellular carcinoma and focal hepatic abscessation are rare in cats. Hepatic abscesses should be included in the differential diagnosis of cats with non-specific signs, even in the absence of biochemical evidence of a hepatopathy.

Retrospective study of feline and canine cryptococcosis in Australia from 1981 to 2001: 195 cases

A retrospective study of 155 cats and 40 dogs diagnosed with cryptococcosis between 1981 and 2001 was undertaken. Age, sex, breed, clinical findings, feline immunodeficiency virus and feline leukaemia virus status (in cats), species of Cryptococcus causing disease and region of domicile were recorded. Associations between variables were tested. Male and female cats were affected equally. Age ranged from 1 to 16 years, with a preponderance of cats aged between 2 and 3 years. Siamese, Himalayan and Ragdoll breeds were over-represented. Rural cats were more frequently infected with Cryptococcus gattii. Retroviral infection was not identified as a predisposing condition and was not correlated with either species of Cryptococcus or physical findings. Most cats had signs of nasal cavity infection, which was typically localised for a substantial period before invasion of adjacent structures or dissemination. Male and female dogs were affected equally. A marked preponderance of young, large breed dogs was noted. Border Collies, Boxers, Dalmatians, Dobermann Pinschers, Great Danes and German Shepherds were over-represented. Cryptococcus species involved was not affected by place of domicile. Although nasal cavity involvement was important, the canine cohort had a greater propensity to develop secondary central nervous system involvement and disseminated disease than feline cases. There were no clinical findings in either cats or dogs which could be reliably used to distinguish disease caused by Cryptococcus neoformans variety grubii from disease caused by Cryptococcus gattii. Both Cryptococcus species appear to be primary pathogens of cats and dogs, with the upper respiratory tract presumed to be the predominant primary site of inoculation in most but not all cases.