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D I Wigney

Publications and source records attributed to D I Wigney.

30 records · Page 2Linked to original sources
PubMed1997

Nasopharyngeal cryptococcosis.

Naturally occurring cryptococcosis in five cats, a dog and a koala is described. Involvement of the nasopharynx was documented in all patients, and nasopharyngeal mass lesions accounted for the major presenting complaints in four. Signs referable to nasopharyngeal disease included snoring, stertor, inspiratory dyspnoea and aerophagia. Diagnoses were made by caudal rhinoscopy using a retroverted flexible endoscope, vigorous orthograde flushing with saline, or at necropsy. Concurrent cryptococcal rhinitis was present in all cases, although involvement appeared limited to the caudal nasal cavity in most cases. Typical signs of nasal cavity disease, such as sneezing and nasal discharge, were often absent. Treatment of nasopharyngeal cryptococcosis should include physical dislodgement or debulking of lesion(s) to provide immediate alleviation of upper airway obstruction, followed by systemic antifungal therapy to eliminate residual infection from the nasal cavity. Infections caused by Cryptococcus neoformans var gattii accounted for a disproportionately large number of these cases.

Animals↗
PubMed1996

Combination chemotherapy of canine and feline cryptococcosis using subcutaneously administered amphotericin B.

Six cases (3 cats, 3 dogs) of cryptococcosis were cured using combination chemotherapy that included amphotericin B. We developed a simple, practical and inexpensive method of administering amphotericin B as a subcutaneous infusion during the treatment of these patients. For this, the calculated dose of amphotericin B (0.5 to 0.8 mg/kg) was added to 400 mL, for cats, or to 500 mL, for dogs, of 0.45% saline containing 2.5% dextrose. These amounts were given subcutaneously 2 or 3 times weekly over several months, to a total cumulative dose of 8 to 26 mg/kg body weight. Subcutaneous infusions were generally well tolerated by the animals, although concentrations of amphotericin B in excess of 20 mg/L resulted in local irritation. This protocol enabled the administration of larger, and thus more effective, quantities of amphotericin B without producing marked azotaemia.

Amphotericin B↗
PubMed1996

Suspected drug eruption in seven dogs during administration of flucytosine.

7 of 8 dogs receiving combination drug therapy consisting of flucytosine together with amphotericin B and/or a triazole for cryptococcosis or aspergillosis developed cutaneous or mucocutaneous eruptions during the course of treatment. Lesions resolved in all cases following discontinuation of flucytosine despite continued administration of other antifungals, suggesting the eruption was referable primarily to the flucytosine component of therapy. Lesions developed 13 to 41 days (median 20 days) after commencing flucytosine (105 to 188 mg/kg/day divided and given every 8 h; median dose rate 150 mg/kg/day). The cumulative dose of flucytosine given prior to the first signs of the drug eruption ranged from 1.7 to 6.8 g/kg (median 2.3 g/kg). The eruptions consisted of depigmentation, followed by ulceration, exudation and crust formation. The scrotum was affected in all 4 male dogs, the nasal plane in 6 of 7 cases, while the lips, vulva, external ear canal and integument were involved in a smaller number of cases. There was considerable variation in the severity of lesions, with changes being most marked when flucytosine was continued for several days after lesions first appeared. Some dogs experienced malaise and inappetence in association with the suspected drug eruption. Healing took a variable period, typically in excess of 2 weeks after discontinuing flucytosine, with up to 2 months being required for total resolution of the lesions. All lesions resolved eventually without scarring or permanent loss of pigment.

Amphotericin B↗
PubMed1996

A latex cryptococcal antigen agglutination test for diagnosis and monitoring of therapy for cryptococcosis.

A latex cryptococcal antigen agglutination test (LCAT) was performed on sera obtained during the first 14 days of treatment from 58 animals (46 cats, 9 dogs, 2 koalas and 1 long billed corella) with cryptococcosis. The same commercial kit was used for all samples, and most serum samples were treated with pronase before testing. Sera from all 58 cases tested positive with the qualitative LCAT protocol (using undiluted sera), while sera from all 26 cats without cryptococcosis tested negative. Titres determined using the quantitative protocol ranged from 1 to > or = 131 072 (median titre between 2048 and 4096), with 57 of 58 cases (including all 8 animals that presented for neurological signs) having titres > or = 2 and thus considered positive according to the manufacturer's recommendations. The LCAT titre was positively correlated with disease severity (r = 0.4169; P = 0.0011), and patients with disseminated skin and/or lymph node involvement had significantly higher titres than those that did not (P = 0.0157). The presence of neurological signs, the species of the patient, concurrent viral disease (in cats) and the biotype of the isolate had no significant association with the LCAT titre. Cats that died of active cryptococcosis despite treatment did not have significantly higher titres (P = 0.3010) than those that responded to treatment. Sequential LCAT determinations obtained in 37 patients during treatment provided a useful quantitative indication of clinical progress, although the decline in titre lagged somewhat behind clinical improvement. Generally, the antigen titre declined by 2 to 4 fold per month during successful therapy. Although there are insufficient data to make unequivocal recommendations, we suggest that either antifungal therapy be continued until the LCAT titre declines to less than 1, or therapy be discontinued after a 32 fold or greater reduction in titre, with periodic monitoring of the serum antigen titre. Treatment of serum samples with pronase substantially increased the sensitivity of the LCAT.

Agglutination Tests↗
PubMed1994

Porphyromonas canoris sp. nov., an asaccharolytic, black-pigmented species from the gingival sulcus of dogs.

A new species, Porphyromonas canoris, is proposed for black-pigmented asaccharolytic strains isolated from subgingival plaque samples from dogs with naturally occurring periodontal disease. This bacterium is an obligately anaerobic, nonmotile, non-spore-forming, gram-negative, rod-shaped organism. On laked rabbit blood or sheep blood agar plates, colonies are light brown to greenish brown after 2 to 4 days of incubation and dark brown after 14 days of incubation. Colonies on egg yolk agar and on nonhemolyzed sheep blood agar are orange. The cells do not grow in the presence of 20% bile and have a guanine-plus-cytosine content of 49 to 51 mol%. The type strain is VPB 4878 (= NCTC 12835). The average levels of DNA-DNA hybridization between P. canoris strains and other members of the genus Porphyromonas are as follows: Porphyromonas gingivalis ATCC 33277T (T = type strain), 6.5%; Porphyromonas gingivalis cat strain VPB 3492, 5%; Porphyromonas endodontalis ATCC 35406T, 1%; Porphyromonas salivosa NCTC 11362T, 5%; and Porphyromonas circumdentaria NCTC 12469T, 6%. The level of hybridization between P. canoris NCTC 12835T DNA and Porphyromonas asaccharolytica ATCC 25260T DNA is 3%. P. canoris cells produce major amounts of acetic, propionic, isovaleric, and succinic acids and minor amounts of isobutyric and butyric acids as end products of metabolism in cooked meat medium. The major cellular fatty acid is 13-methyltetradecanoic acid (iso-C15:0). Glutamate and malate dehydrogenases are present, as are glucose-6-phosphate dehydrogenase activity (65.7 nmol mg of protein-1 min-1) and 6-phosphogluconate dehydrogenase activity (63.0 nmol mg of protein-1 min-1).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Phylogenetic analysis of members of the genus Porphyromonas and description of Porphyromonas cangingivalis sp. nov. and Porphyromonas cansulci sp. nov.

The partial 16S rRNA gene sequences of representative strains of two groups of anaerobic, gram-negative, pigmented, asaccharolytic, rod-shaped bacteria isolated from subgingival plaque of dogs with naturally occurring periodontal disease were determined. A comparative analysis of the rRNA sequence data revealed that the two groups of organisms represent previously unknown lines of descent within the genus Porphyromonas. On the basis of our phylogenetic findings and the phenotypic distinctiveness of the organisms, two new species, Porphyromonas cangingivalis and Porphyromonas cansulci, are proposed.

Base Composition↗
PubMed1992

Cryptococcosis in cats: clinical and mycological assessment of 29 cases and evaluation of treatment using orally administered fluconazole.

Twenty-nine cats with naturally occurring cryptococcosis were evaluated prior to commencing oral fluconazole therapy (25-100 mg every 12 h). Affected cats ranged from 2 to 15 years-of-age. Male cats (19; 66%) and Siamese cats (5; 21%) appeared to be over-represented in comparison to the hospital's cat population. Mycotic rhinitis was observed in 24 (83%) of the cases, although nasal cavity involvement was subtle in four animals. Disease of the skin and subcutaneous tissues was present in 15 cases (52%) and amongst these the nasal plane (seven cats) and bridge of the nose (seven cats) were most commonly involved. Primary infection of the central nervous system was not encountered, although one cat developed meningoencephalitis and optic neuritis as a sequel to longstanding nasal cavity disease. Antibodies against the feline immunodeficiency virus (FIV) were detected in eight cats (28%), and these cats tended to have advanced and/or disseminated disease. There was a tendency for cats to develop cryptococcosis during the Australian summer. Organisms were cultured from 27 cases. Cryptococcus neoformans var. neoformans was isolated from 21 cats, while C. neoformans var. gattii was identified in the remaining six. The response to oral fluconazole was excellent in this series, which included many cats with advanced, longstanding or disseminated disease. The fungal infection resolved in all but one advanced case which died after only 4 days of therapy. A dose of 50 mg per cat, given every 12 h, produced a consistently good response without side effects. Lower doses were effective in some cases, while 100 mg every 12 h was required to control the infection in one cat. Serum fluconazole levels obtained during chronic dosing (50 +/- 18 mg l-1, mean +/- SD; 50 mg per cat every 12 h) were highly variable (range 15-80 mg l-1). Concurrent FIV infection did not impart an unfavourable prognosis, although affected cats often required prolonged courses of therapy.

Animals↗
PubMed1989

Pyogranulomatous pneumonias due to Nocardia asteroides and Staphylococcus epidermidis in two koalas (Phascolarctos cinereus).

Pyogranulomatous pneumonia was detected in two koalas (Phascolarctos cinereus). Nocardia asteroides was isolated from one koala with extensive pneumonia, pleurisy and splenitis. Staphylococcus epidermidis was isolated from a second koala with pneumonia restricted to the left cranial lobe. Both koalas were in poor condition and had underlying urogenital disease. It was concluded that each organism had acted as an opportunistic pathogen in its compromised host.

Animals↗
PubMedDate not supplied

Cryptococcosis in dogs: a retrospective study of 20 consecutive cases.

The clinical and mycological findings in 20 consecutive cases of cryptococcosis evaluated between 1981 and 1995 were analysed retrospectively. Typically, young adult dogs (median age 2 years) of either sex were affected. Dobermann Pinschers and Great Danes were significantly over-represented in relation to other breeds and crossbred dogs, and there was no trend for cryptococcosis to be acquired at a particular time of year. Cryptococcus neoformans was cultured from 18 dogs, with 16 isolates further characterized. Of these, C. neoformans var. neoformans was isolated from 12 cases, while the remaining four strains were C. neoformans var. gattii. Dogs with C. neoformans var. gattii infections resided in rural (two cases) or suburban (two cases) environments. Ten dogs were presented as a result of infection of structures inside, adjacent to, or contiguous with the nasal cavity. Seven dogs were presented primarily for signs of central nervous system disease, of which at least three also had cryptococcal rhinosinusitis. One dog had cryptococcal pneumonia and also possible mycotic rhinitis, another had disseminated disease with lymph node and skin involvement, while the last dog was presented for vomiting referable to cryptococcal mesenteric lymphadenitis. Treatment consisting of surgery and/or antifungal drug therapy was successful in the majority of animals in which it was attempted, including two of three cases with meningo-encephalitis.

Animals↗
PubMedDate not supplied

Susceptibility of bacteria from feline and canine urinary tract infections to doxycycline and tetracycline concentrations attained in urine four hours after oral dosage.

OBJECTIVES: To measure urinary concentrations of doxycycline in cats and dogs and tetracycline in dogs 4 h after conventional oral dosing and determine whether these antibiotics were present in sufficient concentrations to be effective against common feline and canine urinary tract pathogens as assessed in vitro by Epsilometer and disc diffusion antimicrobial susceptibility methods. DESIGN: A prospective study involving oral administration to clinically normal cats and dogs of doxycycline or tetracycline (dogs only) and culture of bacteria from dogs and cats with urinary tract infections to determine their susceptibility to both doxycycline and tetracycline in vitro. PROCEDURE: In the first study, nine cats and eight dogs were administered doxycycline monohydrate (5 mg/kg every 12 h) and a further eight dogs were administered tetracycline hydrochloride (20 mg/kg every 8 h) for 72 h. Blood was collected at 2 and 4 h, and urine at 4 h, after the last dose. The concentration of each agent in serum and urine was determined by modified agar diffusion. In the second study, 45 urine samples from cats and dogs with urinary tract infections were cultured. Every bacterial isolate was tested in vitro using both Epsilometer (doxycycline and tetracycline) and disc diffusion (doxycycline, tetracycline or amoxycillin-clavulanate) tests. RESULTS: Serum doxycycline concentrations in sera of cats and dogs at 2 h were 4.2 +/- 1.0 mg/mL and 3.4 +/- 1.1 mg/mL, respectively. The corresponding concentrations at 4 h were 3.5 +/- 0.7 mg/mL and 2.8 +/- 0.6 mg/mL. Urinary doxycycline concentrations at 4 h (53.8 +/- 24.4 mg/mL for cats and 52.4 +/- 24.1 mg/mL for dogs) were substantially higher than corresponding serum values. Serum tetracycline concentrations in dogs at 2 and 4 h, and in urine at 4 h, were 6.8 +/- 2.8, 5.4 +/- 0.8, 144.8 +/- 39.4 mg/mL, respectively. Most of the urinary tract pathogens (35/45) were susceptible to urinary concentrations of doxycycline and 38/45 were susceptible to tetracycline. In contrast 41/45 of all isolates were susceptible to amoxycillin-clavulanate. CONCLUSION: This is the first report of urinary concentrations of doxycycline after conventional oral administration. Concentrations attained in the urine of normal cats and dogs were sufficient to inhibit the growth of a significant number of urinary tract pathogens and thus doxycycline may be a useful antimicrobial agent for some urinary tract infections.

Administration, Oral↗
PubMedDate not supplied

Asymptomatic carriage of Cryptococcus neoformans in the nasal cavity of dogs and cats.

Nasal washings, obtained from a random source of dogs and cats, were concentrated by centrifugation and plated onto bird seed agar containing antibiotics. Cryptococcus neoformans var. neoformans was isolated from eight of 56 dogs (14%) and three of 45 cats (7%). More than 100 colonies of C. neoformans were present on the plates from seven of the 11 positive animals. Absence of cryptococcal antigen in the serum of these animals, and failure to demonstrate yeast-like organisms or significant pathology in nasal biopsies, suggests that the nasal cavity of these animals was not infected by C. neoformans but rather that blastoconidia and/or basidiospores were carried asymptomatically. These findings are discussed in relation to the likelihood of the upper respiratory tract being the primary site for cryptococcal infection in dogs and cats.

Animals↗