Suppurative intracranial processes in 15 domestic ruminants

Brain Abscesses in Domestic Ruminants: Clinicopathological and Bacteriological Approaches

Brain abscesses in ruminants often arise from primary infection foci, leading to an unfavorable prognosis for affected animals. This highlights the need for comprehensive studies on brain abscesses across different ruminant species. We retrospectively investigated medical records of epidemiological, clinical, neuroimaging, anatomopathological, and bacteriological findings in six ruminants (three goats, two cows, and one sheep) diagnosed with brain abscesses. All animals studied were female. Apathy (50%), compulsive walking (33%), decreased facial sensitivity (33%), head pressing (33%), seizures (33%), semicomatous mental status (33%), strabismus (33%), unilateral blindness (33%), and circling (33%) represented the most common neurologic signs. Leukocytosis and neutrophilia were the main findings in the hematological evaluation. Cerebrospinal fluid (CSF) analysis revealed predominant hyperproteinorrachia and pleocytosis. In three cases, computed tomography or magnetic resonance imaging were used, enabling the identification of typical abscess lesions, which were subsequently confirmed during postmortem examination. Microbiological culture of the abscess samples and/or CSF revealed bacterial coinfections in most cases. Advanced imaging examinations, combined with CSF analysis, can aid in diagnosis, although confirmation typically relies on postmortem evaluation and isolation of the causative agent. This study contributes to clinicopathological aspects, neuroimages, and bacteriological diagnosis of brain abscesses in domestic ruminants.

Suppurative Meningoencephalitis by Pseudomonas aeruginosa from Direct Extension of Chronic Otitis in a Gir Cow

This paper aims to report clinical, laboratory and pathological features in a case of suppurative meningoencephalitis by P. aeruginosa from the direct extension of chronic otitis in a Gir cow. The cow was recumbent during physical examination, and neurological examination revealed depression, absence of left eyelid and auricular motor reflex, and hypotonic tongue. Hematology revealed hemoconcentration, leukocytosis by neutrophilia, and hyperfibrinogenemia. Cerebrospinal fluid was slightly turbid, and presented polymorphonuclear pleocytosis, and hyperproteinorrachia. Grossly, the skull floor showed a purulent green-yellow exudate that drained from the left inner ear to the cisterna magna. There was diffuse congestion of the telencephalon, and meninges showed severe hyperemia, moderate thickening, and opacity with the deposition of fibrinosuppurative material ventrally, extending to the cerebellum and brainstem. The left cerebellar hemisphere showed an approximately 1.5 cm in diameter liquefaction area surrounded by a hemorrhagic halo. Histologically, cerebellar, mesencephalic, thalamic, and brain base meninges were intensely thickened and showed severe suppurative inflammation and fibrin deposition. Small multifocal suppurative areas were observed in the cerebellum and brainstem, characterized by a necrotic core, a number of neutrophils, and Gram-negative intralesional bacillary myriads. Pure cultures of P. aeruginosa were obtained and identified in the suppurative CNS lesions, meninges, and inner ear samples. This report highlights an uncommon clinical evolution of secondary P. aeruginosa suppurative meningoencephalitis, probably triggered by recurrent parasitic otitis in an adult Gir cow. Veterinarians, practitioners, and farmers must be aware of the risk of CNS infections after unresolved media and inner otitis, especially in cattle breeds more prone to developing parasitic otitis, such as the Gir and Indubrasil breeds.

Compressive lesions in the central nervous system of cattle: a retrospective study of 50 cases in the Amazon biome

ABSTRACT: The present study gathered epidemiological and clinical-pathological information about cattle with compressive lesions in the central nervous system (CNS). The retrospective study included observations made in 50 cattle from 1998 to 2021 by reviewing the clinical records of animals with compressive lesions in the CNS treated at the Veterinary Hospital of the Veterinary Medicine Institute of the Federal University of Pará. The animals had clinical signs and were subjected to general and specific clinical examination of the nervous system. Blood samples were collected from 13 animals for complete blood counts, and cerebrospinal fluid (CSF) samples were collected from four animals for physical evaluation. Twenty-nine cattle underwent necropsy. The most affected sites were the T3-L3 (46%, 23/50), C1-C5 (22%, 11/50), C6-T2 (14%, 7/50), sacrococcygeal vertebrae, (4%, 2/50), L4-S2 (2%, 1/50), brain (8%, 4/50) and cerebellum (4%, 2/50). The age of the affected cattle ranged from 20 days to 16 years, with a higher occurrence in animals younger than 12 months (56%, 28/50). More Females were affected (58%, 29/50) than males (42%, 21/50). The clinical signs varied according to the location of the lesion and were mainly represented by ataxia, paresis or paralysis of the limbs, inability to stand and walk, postural changes, hyperesthesia in the extremities, and loss of skin sensitivity at the location of the lesion. The necropsy findings revealed changes such as abscesses in the vertebral body; intervertebral space in the medullary canal, pituitary and cerebellum; granuloma in the arch of the vertebra; fractures of the body of the vertebrae; subarachnoid haematoma; congenital bone alteration causing spinal cord compression; and spondylitis. Detailed anamnesis and clinical examination of the CNS, associated with necropsy findings, were important to determine the cause of the disease, correlate with the clinical picture and locate the affected segments of the CNS in the cattle. It is important to include these diseases in the list of differential diagnoses in cattle with nervous symptoms.

Compressive lesions in the central nervous system of buffaloes

ABSTRACT: This study describes, through a retrospective study, the epidemiological and clinical-pathological findings of compression in the central nervous system (CNS) of buffaloes. The study includes observations made in 15 animals from 1998 to 2021 by reviewing the clinical records of animals with compressive injuries of the CNS treated at the Veterinary Hospital of the Veterinary Medicine Institute of the Federal University of Pará. The animals treated with clinical signs compatible with CNS compressive lesions were subjected to general and specific clinical examinations of the nervous system. Blood samples were collected from four animals for complete blood counts, and cerebrospinal fluid (CSF) samples were collected from three animals for physical evaluation. Thirteen animals were necropsied. The age range of the affected animals ranged from four months to 11 years of age, with a greater frequency over age 12 months (80%, 13/15). The most affected vertebral segment was between T3 and L3 (60%, 9/15), followed by brain injury (20%, 3/15), the L4-S2 segment (13.3%, 2/15) and the C1-C5 segment (6.7%, 1/15). The clinical findings varied according to the location of the lesion. The necropsy findings revealed paraypophyseal abscess in the brainstem and vertebral body, subarachnoid hematoma, lymphoma and vertebral fractures. The performance of a thorough clinical examination of the CNS combined with the necropsy findings was important to characterize the clinical picture and to locate the cause and the affected CNS segments in the buffaloes studied. It is important to include CNS compressive lesions among the neurological diseases of buffaloes.

Cerebrospinal fluid analysis in 58 ruminants showing neurological disorders

ABSTRACT: Ruminants may be affected by a wide variety of central nervous system (CNS) diseases. Cerebrospinal fluid (CSF) analysis forms the basis for ante mortem diagnostic evaluation of ruminants with clinical signs involving the CNS. Despite its importance as a tool to aid diagnosis, data regarding CSF examinations in spontaneous cases of CNS diseases in ruminants from Brazil are limited, and most reports involve experimental studies. Therefore, this study aimed to report the results of CSF analysis in 58 ruminants showing signs of neurological disorders. CSF samples for analysis were obtained from 32 cattle, 20 sheep, and 6 goats by cerebello-medullary cistern (n=54) or lumbosacral space (n=4) puncture. These ruminants showed neurological signs related to viral (n=13), mycotic (n=3), or bacterial (n=15) infections, and toxic (n=21), traumatic (n=4), or congenital disorders (n=2). CSF analysis from ruminants with viral infections presented lymphocytic pleocytosis, even though CSF showed no changes in several cases of rabies. Neutrophilic pleocytosis, cloudiness, presence of fibrin clots, and abnormal coloration were evident in the CSF of most cases of CNS bacterial infection, such as meningoencephalitis, meningitis, abscesses, myelitis, and a case of conidiobolomycosis. On the other hand, CSF was unchanged in most cases of toxic disorders, as botulism and hepatic encephalopathy. Elevated CSF density was observed in 60% of ruminants diagnosed with polioencephalomalacia. Our findings show that evaluation of CSF is a valuable diagnostic tool when used in association with epidemiological, clinical and pathological findings for diagnosis of CNS diseases in ruminants.

Suppurative infectious diseases of the central nervous system in domestic ruminants

ABSTRACT: This study describes suppurative infectious diseases of the central nervous system (CNS) in domestic ruminants of southern Brazil. Reports from 3.274 cattle, 596 sheep and 391 goats were reviewed, of which 219 cattle, 21 sheep and 7 goats were diagnosed with central nervous system inflammatory diseases. Suppurative infectious diseases of the CNS corresponded to 54 cases (28 cattle, 19 sheep and 7 goats). The conditions observed consisted of listerial meningoencephalitis (8 sheep, 5 goats and 4 cattle), suppurative leptomeningitis and meningoencephalitis (14 cattle, 2 goats and 1 sheep), cerebral (6 cattle and 2 sheep), and spinal cord (7 sheep) abscesses, and basilar empyema (4 cattle and 1 sheep). Bacterial culture identified Listeria monocytogenes (9/54 cases), Escherichia coli (7/54 cases), Trueperella pyogenes (6/54 cases) and Proteus mirabilis (1/54 cases). All cases diagnosed as listeriosis through histopathology yielded positive immunostaining on immunohistochemistry, while 12/17 of the cases of suppurative leptomeningitis and meningoencephalitis presented positive immunostaining for Escherichia coli. Meningoencephalitis by L. monocytogenes was the main neurological disease in sheep and goats, followed by spinal cord abscesses in sheep. In cattle, leptomeningitis and suppurative meningoencephalitis was the most frequent neurological disease for the species, and E. coli was the main cause of these lesions. Basilar empyema, mainly diagnosed in cattle, is related to traumatic injuries, mainly in the nasal cavity, and the main etiologic agent was T. pyogenes.