Ophthalmic findings associated with Australian tick paralysis (holocyclotoxicity) in hospitalized domestic dogs and cats

OBJECTIVE

To describe ophthalmic findings in hospitalized canine and feline patients with tick paralysis (TP) and investigate possible predisposing factors.

ANIMALS STUDIED

Forty-seven dogs and 28 cats hospitalized with TP assessed with an ophthalmic examination performed by an ABVO resident.

METHODS

Dogs and cats were hospitalized with TP from October 2021 to January 2022 and had an ophthalmic examination performed by an ABVO resident. Patient signalment data, information regarding tick number and location, hospitalization duration, medications used, and patient paralysis grades were recorded. Statistical analysis was performed to correlate findings.

RESULTS

Corneal ulcers developed in up to 34.8% of dogs and up to 42.9% of cats hospitalized with TP. An absent palpebral reflex ipsilaterally increased the odds of a concurrent corneal ulcer being present by 14.7× in dogs and 20.1× in cats (p < .0001). Palpebral reflexes were absent in 38.3% of dogs and 35.7% of cats hospitalized with TP and were correlated with more severe gait paralysis (p = .01) and respiratory paralysis (p = .005) in dogs, and respiratory paralysis in cats (p = .041). STT-1 findings <10 mm/min were present in 27.7% of dogs and 57.1% of cats examined and were associated with increasing gait paralysis (p = .017) and respiratory paralysis (p = .007) in dogs, and increasing gait paralysis in cats (p = .017).

CONCLUSIONS

Simple corneal ulcers, loss of a complete palpebral reflex, and reduced STT-1 scores frequently occurred in dogs and cats hospitalized for TP. The frequency of these findings increased as the degree of patient paralysis increased.

Feline distichiasis treated with cryoepilation: A retrospective study of 15 cats (27 eyes)

OBJECTIVE

To describe the clinical features of cats diagnosed with distichiasis and report on the outcomes following cryoepilation.

ANIMALS STUDIED

Fifteen cats (27 eyes).

PROCEDURES

Medical records of domestic cats with distichiasis that underwent a double freeze-thaw cycle with a -80°C cryoprobe applied to the palpebral conjunctiva, with hair then epilated were retrospectively studied. The patient signalment, distichiae locations, concurrent ocular diseases, recurrences, complications, and outcomes were recorded.

RESULTS

The mean (std dev) age at the time of diagnosis and treatment was 2.2 years (2.8 years). All (15/15) cats were of the domestic shorthair (DSH) breed. Concurrent ocular findings at the initial examination were observed in 17/27 (63%) eyes, with upper lateral eyelid hypoplasia the most prevalent, present in 9/27 (33.3%) eyes. Recurrence of distichiae occurred in 8/27 (29.6%) eyes. The clinical presentation in the instances of recurrence was judged as asymptomatic and not of a clinical concern in 3/27 (11.1%) eyes, with a second procedure deemed necessary to alleviate symptoms in 5/27 (18.5%) eyes. All eyes treated with a second procedure had no recurrence of distichiae or symptoms. Complications following cryoepilation occurred in 4/27 (14.8%) eyes, with two cats developing bilateral entropion post-procedure.

CONCLUSIONS

Treatment of distichiasis in cats utilizing cryoepilation was effective at alleviating symptoms, though some cats needed a second procedure. The development of post-procedural entropion was seen occasionally.

Retrospective assessment of ophthalmic disease development in domestic dogs and cats when hospitalised with tick paralysis caused by Ixodes holocyclus

OBJECTIVE

To investigate the incidence and predisposing factors leading to the development of corneal ulcers and the loss of a palpebral reflex in hospitalised canine and feline patients with tick paralysis (TP).

ANIMALS STUDIED

A total of 102 dogs and 100 cats retrospectively were assessed from previously hospitalised patients.

METHODS

A retrospective cohort study was performed on 102 different canine and 100 different feline patients who were hospitalised for TP from October 2020-January 2022. Patient data were collected, and logistic regression was conducted to determine factors affecting the palpebral reflex and the development of corneal ulcers.

RESULTS

Corneal ulcers occurred in 23/102 (22.5%) dogs during hospitalisation and were strongly associated with an incomplete palpebral reflex ipsilaterally during hospitalisation (P < 0.001), hospitalisation ≥3 days (P = 0.004), mechanical ventilation ≥3 days (P = 0.015) or a tick location cranial to C1 (P = 0.003). An incomplete palpebral reflex during hospitalisation was observed in 29/102 (28.4%) dogs and was significantly associated with decreasing patient weight (P = 0.018), increasing days hospitalised (P = 0.001), having a tick found cranial to C1 (P = 0.004), highest recorded GP grade (P = 0.01), highest recorded RP grade (P = 0.005), use of amoxycillin-clavulanic acid during hospitalisation (P = 0.002) and use of piperacillin/tazobactam during hospitalisation (P = 0.003). There was a significant association between the loss of a complete palpebral reflex and mortality during hospitalisation in dogs (OR = 4.5, P = 0.029). Corneal ulcers occurred in 10/100 (10.0%) cats during hospitalisation, and was significantly more likely to occur to an eye if an incomplete palpebral reflex was observed ipsilaterally during hospitalisation (OR = 20.1, P < 0.0001) and with increasing patient age (P = 0.019). The absence of a complete palpebral reflex during hospitalisation was observed in 18/10 (18.0%) cats and was significantly associated with increasing days hospitalised (P = 0.034). There was no significant association between the loss of a complete palpebral reflex and mortality during hospitalisation in cats.

CONCLUSIONS

The frequency of corneal ulcers and loss of palpebral reflexes were significant in dogs and cats hospitalised by TP, with many factors contributing to the risk of these developing.

Sutural bone frequency in synostotic rabbit crania

This study tests the hypothesis that crania with synostosed sutures will have a significantly higher incidence of calvarial sutural bones than normal crania. Sutural bones were counted in seven calvarial sutures and compared among four groups of adult New Zealand white rabbit skulls: normal in-colony (NI) controls (N = 14), normal out-colony (NO) controls (N = 12), skulls with familial delayed onset (DO) coronal synostosis (N = 25), and skulls with experimentally immobilized coronal sutures (EI) (N = 20). Comparisons among groups were made with a Kruskal-Wallis one-way ANOVA and between groups with a Mann-Whitney U-test, using a Bonferroni correction for multiple comparisons. Significant differences (P < 0.05) were noted only in the coronal and sagittal sutures, with EI crania having the greatest number of coronal sutural bones; between group differences were undetectable for sagittal sutural bones. A post hoc two-sample binomial test for equal proportions showed that the distribution of coronal sutural bones among individuals across groups was even, while the distribution of sagittal sutural bones was significantly higher in EI crania. These results suggest that altered sutural forces of the calvaria contribute to an increased occurrence of sutural bones. However, the influence of inheritance on increased occurrence of sutural bones cannot be discounted, as reflected in the equivalent number of individuals across groups that possessed coronal sutural bones.

Cross-cultural applicability of contextual family therapy: Iranian and American college students' perceptions of familial and peer relationships

To examine the applicability of Contextual Family Therapy to non-western populations, a measure of the theory's central constructs of Trust/Justice, Loyalty, and Entitlement (the Relational Ethics Scale), was administered to a sample of 50 Iranian and 51 American college students studying in the same U.S. schools. The Iranian students reported significantly more vertical constructs (Familial) Trust/Justice and Entitlement, while the American students reported more horizontal (Closest Friend) Trust/Justice and Loyalty constructs in relationships. Finally, the women (25 of each nationality) in the sample, regardless of nationality, reported significantly greater Loyalty in their horizontal relationships than did men.

Rebound phenomena in Tourette's syndrome after abrupt withdrawal of clonidine. Behavioral, cardiovascular, and neurochemical effects

Following an open trial of clonidine hydrochloride (3 to 8 micrograms/kg/day for 12 weeks), we studied the behavioral, cardiovascular, and neurochemical effects of abrupt clonidine withdrawal in seven patients with Tourette's syndrome aged 9 to 13 years. Five patients showed marked worsening of tics. After reinitiation of clonidine therapy, the time required for patients to return to prewithdrawal levels of tic symptoms ranged from two weeks to four months. Increases in motor restlessness, blood pressure, and pulse rate were also observed over the 72-hour period following abrupt withdrawal of clonidine. Plasma levels of free 3-methoxy-4-hydroxyphenylglycol, homovanillic acid, and urinary excretion of norepinephrine and epinephrine increased during the withdrawal period. Clonidine's effectiveness in Tourette's syndrome may be dependent on changes in dopaminergic as well as adrenergic mechanisms.

Assessment of central dopaminergic function using plasma-free homovanillic acid after debrisoquin administration

Central dopaminergic (DA) function in children and adults was assessed by monitoring plasma-free levels of the dopamine metabolite homovanillic acid (pHVA) before and after a single oral dose and chronic oral administration of debrisoquin. Debrisoquin inhibits peripheral metabolism of dopamine to HVA and does not cross the blood-brain barrier. By reducing peripheral formation of HVA through the use of debrisoquin, the remaining HVA in plasma more accurately reflects central DA activity. Debrisoquin administration resulted in marked reductions of pHVA in each of 12 patients studied. Eleven of the 12 subjects tolerated debrisoquin without physical or behavioral side effects. The debrisoquin administration method appears to be a safe and potentially valid technique for evaluating aspects of central dopaminergic function in children and adults.

Onset of major depression in early adulthood. Increased familial loading and specificity

In a family study of 133 probands with major depression and 82 normal control subjects, and 1,518 of their first-degree relatives, we found a substantial inverse relationship between the age of onset of major depression in the probands and the risk of major depression in their relatives. The relatives of probands whose onset of major depression occurred when they were younger than 20 years of age had the highest risk of major depression, compared with the relatives of probands who had later ages of onset or with the relatives of normal subjects. Probands with an age of onset of 40 years or more had familial loading that was only slightly higher than the families of normal control subjects. Our statistical methods enabled us to examine the relationship of the ages of onset in the probands and their relatives while accounting for possible confounding factors. More studies will be needed to sort out secular changes in the rates of the occurrence of major depression among young persons (cohort effect) from the high familial loading of major depression that has its onset in childhood and adolescence, and to determine whether the specificity of transmission of early-onset depression is the result of a single homogeneous disorder.

Clonidine treatment of neonatal narcotic abstinence syndrome

Clonidine hydrochloride, an alpha 2-adrenergic agonists, was used to treat seven infants who were passively addicted to narcotics because of maternal methadone maintenance. In six of seven infants, the major symptoms of narcotic withdrawal were ameliorated after a total daily oral dose of 3-4 micrograms/kg/day was achieved. One infant failed to respond. No toxic side effects of clonidine were observed at the dosage level used. The results of this pilot study suggest that clonidine may be a safe therapeutic agent for the treatment of neonatal narcotic abstinence syndrome (NNAS). Clonidine treatment of NNAS remains strictly investigational at this time. The relative efficacy and safety of clonidine versus other currently used drug regimens for NNAS also remains to be determined.

Subtypes of depression. Family study perspective

To address the validity of subtype distinctions within a large family study of major depression, probands (N = 133) were classified into several non-mutually exclusive subcategories, including endogenous (n = 89), melancholic (n = 61), autonomous (n = 50), and delusional (n = 21). Age-corrected lifetime rates of depression and subtypes among first-degree relatives were then compared by the proband's depression subtype. Rates of major depression were highest for the relatives of probands with the autonomous and delusional subtypes, and while lower for the relatives of endogenous and melancholic probands, these rates were still higher than for the relatives of the remaining depressed probands or the relatives of normal controls. The depressed relatives of depressed probands with the endogenous, melancholic, autonomous, or delusional subtypes were more likely to have one of these subtypes than the depressed relatives of either the remaining depressed probands or the normal controls.

Appetite disturbance and excessive guilt in major depression. Use of family study data to define depressive subtypes

A post hoc analysis of the relationship between depression in first-degree family members (N = 810) and specific patterns of "endogenous" symptoms in 133 probands with nonbipolar major depression revealed that concomitant appetite disturbance and excessive guilt in the depressed probands was associated with increased rates of major depression among family members. The depressed, interviewed relatives of depressed probands with appetite disturbance and excessive guilt were found to be at a 2.5 greater risk for this same subtype compared with the depressed, interviewed relatives of the remaining depressed probands. These findings suggest that this subtype of depression may "breed true" within these families.