Biomedical subjects

M R Lappin

Publications and source records attributed to M R Lappin.

At least 37 records · Page 2Linked to original sources

PubMed1999

Detection of feline herpesvirus-specific antibodies and DNA in aqueous humor from cats with or without uveitis.

OBJECTIVE: To determine whether uveitis in cats was associated with intraocular production of feline herpesvirus type 1 (FHV-1)-specific antibodies or with detection of FHV-1 DNA in aqueous humor (AH). ANIMALS: 44 cats with idiopathic uveitis, 29 cats with uveitis attributed to Toxoplasma gondii infection, 13 FHV-1 seropositive cats without uveitis, and 9 FHV-1 seronegative cats without uveitis. PROCEDURE: ELISA were used to detect FHV-1-specific antibodies and total IgG antibodies in serum and AH, and the Goldmann-Witmer coefficient (C-value) for intraocular antibody production was calculated. A polymerase chain reaction assay was used to detect FHV-1 DNA in AH. RESULTS: FHV-1 seroprevalence among cats with uveitis was not significantly different from seroprevalence among cats without uveitis. Intraocular FHV-1 antibodies were never detected in cats without uveitis. Significantly more cats with idiopathic uveitis (22/44) or with toxoplasmic uveitis (11/29) had evidence of intraocular antibody production (C-value > 1) than did cats without uveitis. Only cats with idiopathic uveitis had FHV-1 C-values > 8. Among cats with evidence of intraocular antibody production, cats with idiopathic uveitis had a significantly higher median FHV-1 C-value (9.61) than did cats with toxoplasmic uveitis (2.56). Overall, FHV-1 DNA was detected in AH from 12 cats, 11 of which had uveitis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that FHV-1 can infect intraocular tissues of cats and that intraocular FHV-1 infection may be associated with uveal inflammation in some cats.

Alphaherpesvirinae↗

PubMed1999

Detection of Toxoplasma gondii parasitemia in experimentally inoculated cats.

Toxoplasma gondii B1 gene polymerase chain reaction (PCR) amplification utilizing a flanking and nesting reaction was compared to mouse bioassay on feline whole blood samples collected before and after experimental inoculation with T. gondii. Samples were collected from 5 cats prior to inoculation with T. gondii and on days 3, 7, 10, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84, 112, 140, 143, 147, 150, 154, 161, 168, 175, and 182 after inoculation. Cats were challenged with T. gondii orally on day 140. Bioassay was found to be less effective for detection of parasitemia than B1 gene PCR. Parasitemia was detected in all 5 cats by PCR multiple times after primary and challenge inoculation. Detection of T. gondii parasitemia by PCR utilizing the flanking reaction described here may be useful in predicting the oocyst shedding period in individual cats. As none of the cats developed signs of systemic illness, yet were chronically parasitemic, T. gondii whole-blood PCR is not helpful as a diagnostic test for clinical feline toxoplasmosis.

Animals↗

PubMed1998

Polymerase chain reaction for the detection of Toxoplasma gondii within aqueous humor of experimentally-inoculated cats.

The purpose of this study was to determine the temporal appearance of T. gondii in aqueous humor of cats orally inoculated with T. gondii using polymerase chain reaction (PCR) for the detection of the B1 gene. Serum and aqueous humor were collected from five SPF cats prior to oral inoculation with T. gondii and days 7, 14, 21, 28, 42, 84, 140, 147, 154, 161, 168, and 182 after inoculation. Cats were inoculated orally with T. gondii tissue cysts on day 0 and day 140. T. gondii-specific IgM and IgG were measured in serum and aqueous humor from the cats at each sample data. T. gondii B1 gene PCR was performed on all the aqueous humor samples and the amplified DNA was detected by Southern blotting. Chorioretinitis developed in three out of the five cats, but anterior uveitis was not detected. All cats developed T. gondii-specific IgG titers in serum, and had T. gondii-specific IgG C-values > 1 in both eyes at varying times during the study. T. gondii was detected by PCR and Southern blotting in aqueous humor in both eyes of all cats at times varying from days 14-84 after primary inoculation and days 14-42 after challenge inoculation.

Administration, Oral↗

PubMed1998

Hepatocellular toxicosis associated with administration of carprofen in 21 dogs.

A diagnosis of hepatocellular toxicosis attributable to carprofen administration was made in 21 dogs on the basis of development of clinical signs and clinicopathologic abnormalities associated with hepatic disease and histopathologic documentation of hepatic necrosis. Clinical signs of toxicosis were anorexia, vomiting, and icterus. Hyperbilirubinemia and high serum activities of alanine transaminase, alkaline phosphatase, and aspartate transaminase were the most notable clinicopathologic abnormalities. In 7 of 9 dogs in which urinalyses were performed, abnormalities suggestive of renal tubular disease were detected. Clinical course of toxicosis was variable; however, most dogs had resolution of clinical signs and improvement or resolution of biochemical abnormalities with discontinuation of the drug and administration of supportive care. As with any medication, clients should be informed of possible adverse effects and reactions associated with administration of carprofen. In the event of those signs, clients should be instructed to immediately discontinue administration of carprofen to their dog and contact their veterinarian.

Animals↗

PubMed1998

Enzyme-linked immunosorbent assay for detection of feline herpesvirus 1 IgG in serum, aqueous humor, and cerebrospinal fluid.

Feline herpesvirus 1 (FHV) is an important cause of feline ocular and respiratory disease, but the role the virus plays in central nervous system disease of cats has not been explored. The study described here was performed to validate an indirect enzyme-linked immunosorbent assay (ELISA) to detect FHV-specific IgG antibodies for use in feline epidemiologic, ocular, and central nervous system disease studies. The indirect IgG ELISA was applied to serum, aqueous humor, and cerebrospinal fluid from cats. Serum FHV IgG ELISA results were compared with those of serum neutralization in client-owned cats and laboratory-housed cats following vaccination. Of the 100 client-owned cats tested by ELISA, 97 had detectable FHV IgG; 95 had titers >32. The FHV IgG ELISA was more sensitive than serum neutralization and could be used with aqueous humor and cerebrospinal fluid. Cats with inflammatory central nervous system or ocular diseases had significant leakage of serum proteins into aqueous humor and cerebrospinal fluid, necessitating use of cutoff values derived from serum when these fluids were assessed.

Animals↗

PubMed1997

Suspected ehrlichial infection in five cats from a household.

Ehrlichiosis is a poorly recognized condition of cats that may be associated with anemia, leukopenia, thrombocytopenia, or dysproteinemia. Affected cats may have indirect fluorescent antibody titers to Ehrlichia canis and E risticii. We reviewed the clinical evaluation and response to treatment of 5 cats in a household where ehrlichial disease was suspected as the cause of recurrent leukopenias and thrombocytopenias. All of the cats had E risticii indirect fluorescent antibody titers and western blot confirmation of antibodies to 4 of the 9 major antigens of E risticii. Response to doxycycline was monitored serologically and hematologically in each cat, and indicated that administration of doxycycline at a dosage of 10 mg/kg of body weight, PO, every 12 hours, for a minimum of 21 days is necessary for treatment of this condition.

Animals↗

PubMed1997

Elevated interleukin 6 activity in aqueous humor of cats with uveitis.

The purpose of this study was to assess the role of interleukin 6 (IL-6) in feline uveitis by measuring IL-6 activity in the serum and aqueous humor of cats. Serum and aqueous humor was collected from clinically normal, random source cats (n = 10); clinically normal, specific-pathogen free cats experimentally inoculated with Toxoplasma gondii strain ME49 and sampled sequentially for 20 months (n = 4); and client-owned cats with uveitis (n = 27). Interleukin 6 activity was measured in each sample. Client-owned cats with uveitis were also evaluated for evidence of present or prior exposure to T. gondii, feline leukemia virus, feline immunodeficiency virus, and feline coronaviruses. Interleukin 6 activity was non-detectable or low in serum from cats of each group. Interleukin 6 activity was not detected in aqueous humor of clinically normal cats. Interleukin 6 activity was detected in 22/27 (81.5%) aqueous humor samples from cats with uveitis, with a range of 28.9 U ml(-1)-15702.9 U ml(-1) (mean = 1911.9 U ml[-1], SD = 3946.7 U ml[-1]). Serologic evidence of exposure to T gondii, feline immunodeficiency virus, feline leukemia virus, or a coronavirus was present in 21/27 (77.8%) cats with uveitis. Interleukin 6 was detected in the aqueous humor of 18/21 (85.7%) and 3/6 (50%) of the cats with and without serologic evidence of exposure to one to the infectious diseases, respectively. Statistically significant increases in mean IL-6 activity in aqueous humor were found for cats with any evidence of infection with T. gondii, for cats with T. gondii antigen in aqueous humor and for cats with coronavirus antibody titers > or = 1:100. Aqueous humor IL-6 activity was greater than corresponding serum IL-6 activity in 21/27 cats. These results show that IL-6 is produced intraocularly in some cats with uveitis and that IL-6 may be a mediator of uveitis in cats.

Animals↗

PubMed1997

Serologic survey for toxoplasmosis in river otters.

The prevalence of antibody titers to Toxoplasma gondii in river otters (Lutra canadensis) from eastern North Carolina (USA) was investigated in a cross sectional study. Sera from 103 live trapped river otters were tested for antibodies to T. gondii using a commercially available latex agglutination kit. Forty-six (45%) of the sera were positive with titers ranging from 1:16 to > 1:2,048. Adult otters (n = 78) had a seroprevalence of 47% and juvenile otters (n = 25) had a seroprevalence of 39%. Significant differences were not found between the sexes within either maturity class. The high prevalence of antibodies to T. gondii indicates that many animals in this population were exposed to the organism. This suggests handling of otters may be a zoonotic concern for fur trappers.

Animals↗

PubMed1997

Enzyme-linked immunosorbent assay for the detection of Cryptosporidium parvum IgG in the serum of cats.

The objective was to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of Cryptosporidium parvum IgG in the serum of cats. The ELISA was an indirect ELISA using soluble C. parvum oocyst antigens and a peroxidase-labeled anti-feline IgG secondary antibody. Sera from cats with Toxocara felis, Giardia spp., Aelurostrongylus abstrusus, Isospora felis, Isospora rivolta, Toxoplasma gondii, or Taenia spp. infections were assayed in specificity studies. Following optimization, the ELISA and fecal examination for oocysts were performed on samples from 170 client-owned or humane society source cats and 1 cat inoculated orally with C. parvum oocysts. Cryptosporidium parvum oocysts were detected in feces (4/170; 2.4%), and C. parvum IgG was detected in serum (26/170; 15.3%) from naturally exposed cats. The seroprevalence data suggest that some cats in the geographical area studied were exposed to C. parvum, but persistent oocyst shedding was less common. The ELISA is not useful for predicting oocyst shedding in individual cats.

Animals↗

PubMed1996

Clinical and serologic evaluation of cats with cryptococcosis.

OBJECTIVE: To evaluate the long-term clinical outcomes and serologic changes in cryptococcal antigen and antibody titers in cats with confirmed Cryptococcus neoformans infection. DESIGN: Prospective case series. ANIMALS: 47 cats with cryptococcosis. PROCEDURE: Cats included in this study were determined to have cryptococcosis on the basis of identification of C neoformans on histologic or cytologic examination, isolation of C neoformans in culture, or positive serologic test results for cryptococcal antigens. Information concerning the signalment, history, physical examination findings, FeLV and feline immunodeficiency virus status, serologic testing, treatment, and outcome for each cat was requested on a survey form. Follow-up measurements of serum cryptococcal antigen and antibody titers were requested for all surviving cats. RESULTS: Signalment and clinical signs of cats with cryptococcosis reported here were consistent with previous reports. Treatment consisted primarily of azole antifungal drugs. All cats were seronegative for cryptococcal antibody titers, whether tested initially or at follow-up examination. All but 1 cat tested were seropositive for cryptococcal antigens when initially tested. Cats with and without clinical signs of C neoformans infection were seropositive for cryptococcal antigens months to years after initial diagnosis of cryptococcosis. CLINICAL IMPLICATIONS: The results of this study indicate that serum titers to cryptococcal antigens in cats can persist with or without clinical signs for months to years after an initial diagnosis of cryptococcosis is made. Repeated evaluation of serum cryptococcal antigen titers is advised during the treatment of cats to monitor progress, evaluate prognosis, and guide cessation of treatment.

Animals↗

PubMed1996

Feline ocular and cerebrospinal fluid Toxoplasma gondii-specific humoral immune responses following specific and nonspecific immune stimulation.

Toxoplasma gondii-naive cats and cats previously infected orally with T. gondii tissue cysts were inoculated with soluble tachyzoite antigens plus adjuvant or adjuvant alone. Toxoplasma gondii-specific IgM and IgG were measured in serum, aqueous humor, and cerebrospinal fluid (CSF). The Goldman-Witmer coefficient (C value) for ocular or central nervous system (CNS) antibody production was calculated for aqueous humor or CSF samples positive for T. gondii-specific antibodies. Following inoculation with adjuvant plus soluble tachyzoite antigens, ocular and CNS T. gondii-specific IgG C values increased in the three previously infected cats. Following inoculation with adjuvant, the two previously infected cats had increases in ocular and CNS T. gondii-specific IgG C values. Ocular (2/3 cats) or CNS (1/3 cats) T. gondii-specific IgG C values of over 1 were detected in some T. gondii-naive cats following inoculation with adjuvant plus soluble tachyzoite antigens. The results of this study suggest that T. gondii-specific IgG C values of over 1 in aqueous humor or CSF do not prove active ocular or CNS infection in all cats.

Adjuvants, Immunologic↗

PubMed1996

Feline toxoplasmosis: interpretation of diagnostic test results.

Based on seroprevalence studies, approximately 30% of the cats in the United States have been infected by T gondii. Cats are the only species that pass the environmentally resistant oocyst in feces. Sporulated oocysts are infectious to humans and the organism can cause significant disease in immunocompromised people and transplacentally-infected babies. Clinical illness including liver disease, lung disease, central nervous system disease, fever, and uveitis occur in some infected cats. Veterinarians need to be able to identify T gondii infection in cats because of potential public health risks and during the workup of clinical diseased cats. Oocyst shedding by cats is of short duration, but can be detected by fecal examination. There are currently no serological tests that can accurately determine when a cat has shed oocysts in the past. The combination of serological test findings, clinical signs of disease, exclusion of other causes, and response to anti-Toxoplasma drugs is required to make the diagnosis of antemortem++ clinical toxoplasmosis in cats.

Animals↗

PubMed1996

Paradoxical effect of clindamycin in experimental, acute toxoplasmosis in cats.

Cats were experimentally inoculated parenterally with the ME49 strain of Toxoplasma gondii to characterize the efficacies of two different dosages of orally administered clindamycin hydrochloride in the treatment of ocular toxoplasmosis. Concentrations of clindamycin hydrochloride at levels previously suggested to be inhibitory to T. gondii replication in vitro were achieved in the serum and aqueous humor but not in the cerebrospinal fluid. Antibiotic therapy, initiated 7 days after inoculation, resulted in no significant difference in the morphometric severity of ocular posterior segment lesions compared with that in the control groups. Treatment appeared to blunt T. gondii-specific immunoglobulin M production but had no significant effect on immunoglobulin G titers. Paradoxically, clindamycin administration was associated with increased morbidity and mortality from hepatitis and interstitial pneumonia, which are characteristic of generalized toxoplasmosis. Serum tumor necrosis factor alpha activity was detected at moderate levels in all groups of cats and correlated with the severity of clinical disease. The results of the study suggest that clindamycin, when administered at this specific time interval following inoculation, does not ameliorate ocular lesions and has a detrimental effect on the clinical course of acute, experimental toxoplasmosis in cats. The factors responsible for and the relevance of this detrimental effect to naturally occurring toxoplasmosis in humans and pet cats were not clear from the study but may relate to an antibiotic-associated decrease in the antitoxoplasmic activity of phagocytic cells responsible for the control of T. gondii.

Acute Disease↗

PubMed1996

Toxoplasma gondii antigen recognition by serum immunoglobulins M, G, and A of queens and their neonatally infected kittens.

OBJECTIVE: To evaluate antigen recognition patterns of serum IgM, IgG, and IgA from queens and their kittens as a method of diagnosing neonatal toxoplasmosis. ANIMALS: 5 pregnant queens were inoculated orally with Toxoplasma gondii tissue cysts during gestation (18 to 44 days). On various days after parturition (0 to 97), serum was obtained from queens and kittens (n = 19). PROCEDURE: Tissues from most kittens were assessed for T gondii infection by bioassay in mice. Serum samples were evaluated by IgM, IgG, and IgA western blot immunoassays for the presence of T gondii antibodies. Antigens recognized by kitten serum samples, but not by the corresponding queen serum sample, were considered to indicate neonatal infection with T gondii. RESULTS: Using the results of western blot immunoassay, 8 of 19 kittens (age, 2 to 97 days) were determined to be infected with T gondii. Western blot immunoassay results correlated well with bioassay results, identifying 7 of 8 bioassay-positive kittens. Western blot immuno-assay additionally identified 1 kitten as infected, but tissues from the kitten had not been bioassayed. In each of the 5 kittens that developed clinical signs of toxoplasmosis, the diagnosis of neonatal toxoplasmosis was supported by results of the western blot immunoassays. CONCLUSION AND CLINICAL RELEVANCE: Comparison of queen and kitten T gondii antigen recognition patterns of IgM, IgG, and IgA can be used for antemortem diagnosis of neonatal toxoplasmosis.

Animals↗

PubMed1996

Primary and secondary Toxoplasma gondii infection in normal and feline immunodeficiency virus-infected cats.

Normal and asymptomatic feline immunodeficiency virus (FIV)-infected adult cats were inoculated orally with Toxoplasma gondii tissue cysts to assess differences in clinical disease, T. gondii serologic test results, hematologic results, and oocyst shedding. There was no difference between FIV-naive and FIV-infected cats in terms of clinical illness and duration of oocyst shedding following primary exposure. Both groups of cats developed significant decreases in neutrophil counts following primary inoculation with T. gondii; FIV-infected cats that were neutropenic prior to inoculation with T. gondii developed the most profound decreases in neutrophil numbers. Both FIV-naive and FIV-infected cats became lymphopenic during acute T. gondii infection; however, only FIV-naive cats developed lymphocytosis in the recovery stage. FIV-infected cats had lower total CD4+ and higher total CD8+ T-lymphocyte counts than FIV-naive cats prior to inoculation with T. gondii, but changes in these lymphocyte subsets were similar between groups of cats during the first several weeks after inoculation. Toxoplasma gondii infection had neither an ameliorating nor enhancing effect on T-lymphocyte subset abnormalities in FIV-infected cats during acute or chronic infection. Both groups of cats developed comparable levels of T. gondii-specific IgM and IgG antibodies and T. gondii antigen-specific lymphocyte blastogenic responses following primary inoculation. Both groups of cats were fed T. gondii tissue cysts 66 wk following primary exposure and both groups were solidly immune as evidenced by a lack of oocyst shedding and only minor changes in IgM but not IgG antibodies.

Animals↗

PubMed1996

Polymerase chain reaction for the detection of Toxoplasma gondii in aqueous humor of cats.

OBJECTIVES: To develop Toxoplasma gondii B1 gene polymerase chain reaction (PCR) for use with aqueous humor of cats, and to report PCR and antibody detection results in naturally exposed cats with and without uveitis. SAMPLE POPULATION: Serum and aqueous humor samples from client-owned, healthy cats (n = 23) and client-owned cats with uveitis (n = 43). PROCEDURE: T gondii-specific IgM and IgG were measured in serum and aqueous humor from all cats. The Goldman-Witmer coefficient for ocular antibody production was calculated for cats positive for T gondii-specific IgM or IgG in aqueous humor. Aqueous humor from all cats was assessed by the B1 gene PCR. RESULTS: T gondii was detected in aqueous humor by PCR from 2 of 23 (8.7%) healthy cats and 8 of 43 (18.6%) cats with uveitis. T gondii-specific IgM in either serum or aqueous humor was detected in 5 of 8 (62.5%) cats with uveitis and T gondii in aqueous humor. All cats with uveitis and T gondii in aqueous humor had anterior segment disease. In 5 of 8 (62.5%) cats with uveitis and T gondii in aqueous humor, ocular production of T gondii antibodies was not detected. T gondii was not detected in aqueous humor from 14 of 17 (82.4%) cats with ocular production of T gondii-specific antibody. CONCLUSIONS: The presence of T gondii in aqueous humor may correlate to clinical disease in some, but not all, cats. CLINICAL RELEVANCE: T gondii-specific aqueous humor antibody tests and PCR should be used together to aid in the diagnosis of ocular toxoplasmosis in cats.

Animals↗

PubMed1995

Diagnosis of induced toxoplasmosis in neonatal cats.

Sixteen pregnant queens were inoculated orally with tissue cysts of Toxoplasma gondii, and fetal membranes and offspring were examined for T gondii infection by bioassay in mice. Queens appeared clinically normal, although all shed T gondii oocysts. Toxoplasma gondii was isolated from tissues of 7 of 33 fetuses or kittens from 5 litters (at 13, 23, 26, 27, and 29 postinoculation days) from 8 queens euthanatized between 10 and 31 postinoculation days. Infection with T gondii was found in kittens from all 8 litters from the 8 queens that were allowed to undergo parturition and nurse their kittens. A total of 43 kittens were born to these 8 queens. Toxoplasma gondii was isolated from tissues of 26 of 40 kittens bioassayed; in 3 kittens, tissues were not available for bioassay. Toxoplasmosis was severe in full-term kittens born to 5 queens; all 25 kittens from these litters died or were ill by 24 days of age. Anorexia, lethargy, hypothermia, and sudden death were the most common manifestations. Cytologic examination of peritoneal fluid aspirate samples and determination of hepatic-associated enzyme concentrations in affected kittens, as well as measurement of anti-T gondii antibodies in serum of kittens and queens, were helpful in the diagnosis of neonatal toxoplasmosis. Transplacental transfer of anti-T gondii antibodies was not observed in cats. Toxoplasma gondii oocysts were found in fecal samples of 3 kittens from different litters at 16, 24, and 63 days of age.

Agglutination Tests↗

PubMed1995

Evaluation of results of preoperative urodynamic measurements in nine dogs with ectopic ureters.

Cytometrographic studies and urethral pressure profiles were performed to objectively assess the functional status of the urinary bladder and urethra in 9 dogs with congenital ectopic ureters. Functional abnormalities of the urinary bladder or urethra were detected in 8 of 9 (89%) dogs. Cystometrographic evidence of reduced bladder capacity was detected in 4 (44%) dogs, and abnormalities in urethral pressure profiles were consistent with urethral incompetence in 6 (67%) dogs. Dogs with urethral pressure profile abnormalities were treated with phenylpropanolamine hydrochloride, and the urethral pressure profile was reevaluated. Urethral pressure measurements obtained before surgery (3 dogs) and after phenylpropanolamine (6 dogs) were used to predict the likelihood of continence after surgery. Predicted outcomes included continence maintained without medication (3 dogs), continence maintained with phenylpropanolamine (2 dogs), and persistent incontinence despite phenylpropanolamine administration (4 dogs). After surgical repair of ectopic ureters, 2 of 9 (22%) dogs were continent without medication, and 2 (22%) maintained continence with phenylpropanolamine treatment. Various degrees of incontinence persisted in 5 of 9 (56%) dogs, 4 of which had urethral incompetence that had been documented as poorly responsive to phenylpropanolamine administration prior to surgery. Predicted outcomes were consistent with actual outcomes in 8 of 9 (89%) dogs, with predictions of incontinence proving accurate in 4 of 4 (100%) dogs and predictions of continence proving accurate in 4 of 5 (80%) dogs. Urodynamic assessment of dogs with ectopic ureters appears to be valuable for identifying concurrent functional abnormalities of the urinary bladder and urethra and for predicting postoperative outcome.

Animals↗