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James H Meinkoth

Publications and source records attributed to James H Meinkoth.

16 recordsLinked to original sources
PubMed2007

Comparison of core needle biopsy and fine-needle aspiration of enlarged peripheral lymph nodes for antemortem diagnosis of enzootic bovine lymphosarcoma in cattle.

OBJECTIVE: To determine whether antemortem core needle biopsy and fine-needle aspiration of enlarged peripheral lymph nodes could be used to distinguish between inflammation and lymphosarcoma in cattle. DESIGN: Prospective study. ANIMALS: 25 cattle with enlarged peripheral lymph nodes. PROCEDURES: Antemortem biopsies of the selected lymph nodes were performed with an 18-gauge, 12-cm core needle biopsy instrument. Fine-needle aspirates were performed with a 20-gauge, 4-cm needle. Specimens were analyzed by pathologists who were unaware of clinical findings and final necropsy findings, and specimens were categorized as reactive, neoplastic, or nondiagnostic for comparison with necropsy results. RESULTS: Sensitivity and specificity of core needle biopsy ranged from 38% to 67% and from 80% to 25%, respectively. Sensitivity of fine-needle aspiration ranged from 41% to 53%, and specificity was 100%. Predictive values for positive test results ranged from 77% to 89% for core needle biopsy and were 100% for fine-needle aspiration. Predictive values for negative test results were low for both core needle biopsy and fine-needle aspiration. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that core needle biopsy and fine-needle aspiration can aid in the antemortem diagnosis of bovine enzootic lymphosarcoma. Results of fine-needle aspiration of enlarged peripheral lymph nodes were more specific and more predictive for a positive test result than were results of core needle biopsy.

Animals↗
PubMed2006

More than meets the eye: subretinal aspirate from an acutely blind dog.

A 14-year-old, spayed female Cocker Spaniel was presented to the Boren Veterinary Medical Teaching Hospital at Oklahoma State University with acute loss of vision in the right eye and a history of intermittent bloody diarrhea of unknown duration. Small, white, plaque-like lesions in the retina and subretina were visualized by direct ophthalmic examination, and aspirated with ultrasound-guidance. A direct smear of the subretinal fluid was highly cellular and contained large numbers of pleomorphic organisms consistent with Prototheca sp. The structures were round, oval, or elongated, 4-6 microm width and 8-16 microm in length and surrounded by a thin, clear cell wall. Small, central, pink to purple nuclei were observed in some organisms, but in most, the nuclei were obscured by a deeply basophilic, granular cytoplasm. Some organisms contained endospores. Negatively-stained structures of similar size and shape were considered to be empty casings (theca) of ruptured sporulating and nonsporulating forms of the organism. Protothecosis usually is a disseminated, fatal disease in dogs. The Prototheca organisms observed in this case showed characteristic morphology, illustrating the ability to diagnose protothecosis in cytologic samples.

Acute Disease↗
PubMed2006

Cytologic identification of immature endospores in a dog with rhinosporidiosis.

An 8-year-old, intact, male Labrador Retriever was presented to the Boren Veterinary Medical Teaching Hospital at Oklahoma State University with a 2-month history of severe sneezing episodes that resulted in epistaxis and bilateral sanguineous discharge. Rhinoscopy revealed a small polypoid mass, and specimens were obtained for histopathology. Microscopic examination of formalin-fixed tissue specimens revealed organisms consistent with Rhinosporidium seeberi. The mass was surgically excised and impression smears were made for cytology examination. Smears revealed high numbers of endospores, typical of those previously described for R seeberi. In addition, numerous smaller structures, presumed to be immature endospores, were noted. The immature endospores were morphologically distinct from mature endospores and have not been described previously. Recognition of immature forms of Rhinosporidium may help prevent misidentification of the organism or misdiagnosis of a dual infection.

Animals↗
PubMed2005

Feline cytauxzoonosis.

Cytauxzoon felis is a protozoan hemoparasite of wild and domestic cats. In domestic cats, it causes severe clinical disease with high mortality.

Animals↗
PubMed2005

Draining skin lesion from a desert poodle.

A 16-month-old intact female Poodle in Arizona had a history of intermittent coughing of a few weeks duration. Coccidiomycosis antibody screening test results were negative for immunoglobulin (Ig) M, but were positive (1:64) for IgG. Fine needle aspiration specimens of a draining lesion on the right palmar front foot contained large numbers of neutrophils, many of which contained bacteria, and lower numbers of macrophages. A few small structures also were observed, 2-5 microm in diameter with thin, nonstaining capsules and small, round to oval densely aggregated, eccentric nuclei. Cytologic findings were consistent with septic pyogranulomatous inflammation with Coccidiodes immitis endospores. Fungal culture of a sample from the draining lesion yielded white growth with barrel-shaped arthroconidia. Identification of the organism as C immitis was confirmed by a commercial DNA probe test. Although coccidioidomycosis often is diagnosed by microscopic identification of C immitis spherules in cytologic specimens, in this case only endospores, which are released from mature spherules, were observed. In cases of suspected coccidiodomycosis, the unique morphology of endospores may be useful in making a cytologic diagnosis.

Animals↗
PubMed2005

A new species of Cytauxzoon from Pallas' cats caught in Mongolia and comments on the systematics and taxonomy of piroplasmids.

DNA was extracted and the 18S ribosomal RNA gene was amplified and sequenced from the blood of 2 Pallas' cats (Otocolobus manul) infected with small intraerythrocytic piroplasms. Sequences of the parasite were found to be identical with that of a previously reported Cytauxzoon-like piroplasm from a Pallas' cat. Phylogenetic analyses of the parasite DNA sequences obtained from the 3 Pallas' cats to other piroplasms revealed a sister group relationship to C. felis. The mean corrected percent sequence divergence between the Pallas' cat parasite and C. felis was 1.490%, which is greater than that for most other piroplasms in which species status has been accepted. On the basis of the sequence variation, we propose to name the Pallas' cat parasite C. manul. Phylogenetic analyses of C. manul also revealed a close relationship with the Spanish Cytauxzoon-like isolate because they exhibited only 0.389% sequence divergence, yet these sequences exhibit a mean of 1.690% sequence divergence from the New World isolate of C. felis. Our phylogenetic analyses also revealed several taxonomic problems that have impeded the development of a classification that accurately reflects evolutionary history of piroplasms. As currently arranged, Babesia and Theileria are paraphyletic taxa and are in need of reorganization.

Animals↗
PubMed2004

Naturally occurring tularemia in a dog.

A 4-year-old spayed female Irish Setter was examined because of acute onset of lethargy, anorexia, and weakness. The dog had eaten an adult rabbit 36 hours earlier. Tularemia was suspected because of the rabbit exposure; however, other common diseases characterized by fever, malaise, and lymphadenopathy of acute onset were also considered (ie, ehrlichiosis and Rocky Mountain spotted fever). The dog was treated with doxycycline (5 mg/kg [2.3 mg/lb], PO, q 24 h) for 14 days as well as supportive treatment with a balanced electrolyte solution (lactated Ringer's solution [200 mL, SC]). The diagnosis was first established by results of bacteriologic cultures of fine-needle aspirates obtained from lymph nodes and confirmed by results of ELISA and a polymerase chain reaction assay Successful and timely antemortem diagnosis of tularemia in dogs can be accomplished through lymph node aspiration and bacteriologic culture.

Animals↗
PubMed2003

Lymph node cytology.

Lymph node cytology is quick, easy, and rewarding. Cytologic samples of peripheral and/or internal lymph nodes may be collected by fine-needle aspiration biopsy (FNAB) or nonaspiration fine-needle biopsy techniques. In addition, imprints or scrapings may be made from lymph nodes that have been surgically removed or at necropsy. Lymph node cytology is an excellent way to evaluate a lymphadenopathy whether it is a single node enlarged, multiple nodes enlarged, or a generalized lymphadenopathy. If multiple lymph nodes are enlarged, more than one should be sampled. A lymph node away from the mouth or any site of inflammation should be aspirated as well as any lymph node close to a site of inflammation. Generally, if no lymph nodes are enlarged, lymph node cytology is not helpful.

Animals↗
PubMed2003

Experimental Babesia gibsoni infection in coyotes (Canis latrans).

Four 5 mo old captive raised coyotes (Canis latrans) were experimentally inoculated with approximately 1 x 10(6) Babesia gibsoni organisms. Parasites were detected 1 wk post-inoculation in all coyotes with maximum parasitemia of 8-11% occurring at 34 wk. Parasitemias remained at or above 1% for at least 12 wk and were still detectable 20 wk post-inoculation. All experimentally infected coyotes developed pale mucous membranes, splenomegaly, and a positive heme reaction in urine while one coyote exhibited mild depression and inappetence. Infected coyotes also developed a regenerative anemia, thrombocytopenia, and neutropenia. The mild clinical signs coupled with the high level and long duration of parasitemia indicate that coyotes could serve as reservoirs for B. gibsoni. Entrance of this foreign parasite into the United States suggests the need for strict quarantines and thorough health and blood film examinations for imported animals.

Anemia↗
PubMed2002

Clinical and hematologic effects of experimental infection of dogs with recently identified Babesia gibsoni-like isolates from Oklahoma.

OBJECTIVE: To characterize clinical and hematologic responses in dogs following experimental inoculation with Babesia gibsoni-like isolates from infected dogs in Oklahoma. DESIGN: Prospective study. ANIMALS: 6 mixed-breed dogs. PROCEDURE: 2 dogs were inoculated with organisms from a naturally infected dog, and 3 were inoculated with organisms from a second naturally infected dog (1 of these 3 dogs was splenectomized 1 week prior to inoculation). One dog was not inoculated. Complete blood counts were performed weekly. RESULTS: In the 5 dogs inoculated with organisms, parasites were initially detected 1 to 5 weeks after inoculation, and severity of parasitemia peaked with 1.9 to 6.0% of RBC infected by 4 to 6 weeks after inoculation. Parasitemia was easily detectable (> 0.1% of RBC infected) for 3 to 4 weeks. Clinical abnormalities included lethargy, fever, and pale mucous membranes but were mild to nearly inapparent in 2 dogs. All dogs developed regenerative anemia and marked thrombocytopenia. Thrombocytopenia developed before and lasted longer than the parasitemia. Profound but transient neutropenia was detected in some dogs. The splenectomized dog developed more severe parasitemia and anemia and more pronounced clinical abnormalities. Three dogs with intact spleens recovered without treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 2 or more genotypically distinct, but morphologically identical, small Babesia parasites can infect dogs in the United States. Compared with infection with small Babesia parasites from California, infection with these isolates resulted in less severe parasitemia and clinical abnormalities. Parasitemia was transient, indicating that identification of organisms in blood smears may be difficult in some dogs.

Anemia↗
PubMed2002

Recognition of basic cell types and criteria of malignancy.

In-house examination of cytologic preparations can yield timely information and be done with minimal equipment. This article describes the features that allow for recognition of the basic cell types encountered on cytologic smears. General cellular features suggestive of malignancy are covered as well as some common potential pitfalls in their application. These basic concepts can be applied to samples from each of the specific anatomic locations covered in subsequent articles in this issue.

Animal Diseases↗
PubMed2002

Sample collection and preparation in cytology: increasing diagnostic yield.

Cytology is a valuable diagnostic tool for examining many types of lesions. The diagnostic yield of cytology is dependent on optimal sample collection and smear preparation. This article outlines the basic techniques for collection of samples via fine-needle biopsy, imprints, scrapings, and swabs. Tips are given on how to avoid some of the most common problems that lead to nondiagnostic samples.

Animal Diseases↗