Search Results

Abstract

Objective—To detect and characterize the full range of chlamydial infections in cats with ocular disease by use of polymerase chain reaction (PCR) assays, cytologic examination, immunohistochemical analysis, and evaluation of clinical information including status for feline herpesvirus-1 (FeHV-1).

Sample Population—DNA extracted from 226 conjunctival samples obtained from cats with clinically diagnosed keratitis or conjunctivitis and 30 conjunctival samples from healthy cats.

Procedure—PCR assays for the 16S rRNA gene specific for the order Chlamydiales and a new Chlamydophila felis (formerly Chlamydia psittaci) species-specific 23S rRNA gene were performed. Seventy-four conjunctival samples were prepared with Romanowsky-type stain, grouped on the basis of inflammatory pattern, and screened for chlamydial inclusions by use of immunohistochemical analysis. Clinical information and FeHV-1 status were recorded.

Results—26 (12%) specimens had positive results for the only known feline chlamydial pathogen, C felis. Surprisingly, an additional 88 (39%) were positive for non-C felis chlamydial DNA. Identification of non- C felis chlamydial DNA by direct sequencing revealed 16S rRNA gene sequences that were 99% homologous to the sequence for Neochlamydia hartmannellae, an amebic endosymbiont. Chlamydial prevalence was significantly higher in cats with ocular disease.

Conclusions and Clinical Relevance—Application of a broad-range detection method resulted in identification of a new agent associated with ocular disease in cats. Finding chlamydia-like agents such as N hartmannellae in coinfections with their obligate amebic host, Hartmannella vermiformis, raises questions about the potential role of these microorganisms in causation or exacerbation of ocular disease in cats. (Am J Vet Res 2003;64:1421–1428)

Abstract

Objective—To evaluate whether determination of parathyroid gland size by use of ultrasonography is helpful in differentiating acute renal failure (ARF) from chronic renal failure (CRF) in dogs.

Design—Prospective study.

Animals—20 dogs with renal failure in which serum creatinine concentration was at least 5 times the upper reference limit. Seven dogs had ARF, and 13 dogs had CRF. Twenty-three healthy dogs were used as controls.

Procedure—Dogs were positioned in dorsal recumbency for ultrasonographic examination of the ventral portion of the neck, A 10-MHz linear-array high-resolution transducer was used. The size of the parathyroid gland was determined by measuring the maximal length of the gland on the screen when it was imaged in longitudinal section. For comparison among groups, the longest linear dimension of any of the parathyroid glands of each dog was used.

Results—Size of the parathyroid glands in the control dogs varied from 2.0 to 4.6 mm (median, 3.3 mm). In the dogs with ARF, gland size ranged from 2.4 to 4.0 mm (median, 2.7), which was not significantly different from controls. In dogs with CRF, the glands were more distinctly demarcated from the surrounding thyroid tissue, than those of controls and dogs with ARF. Sizes ranged from 3.9 to 8.1 mm (median, 5.7 mm), which was significantly larger, compared with controls and dogs with ARF.

Conclusion and Clinical Relevance—In dogs with severe azotemia, ultrasonographic examination of the parathyroid glands was helpful in differentiating ARF from CRF. Size of the parathyroid glands appeared to be related to body weight. (J Am Vet Med Assoc 2000;217:1849–1852)