An atypical case of respiratory actinobacillosis in a cow

A not pregnant 4-year-old Jersey cow was presented with the sudden appearance of respiratory noise, nasal discharge and moderate respiratory difficulty. Upon physical examination a snoring-like noise, extended head and neck position, exaggerated abdominal effort, bilateral nasal discharge and left prescapular lymph node enlargement were noted. Sub-occlusion of the initial portion of the respiratory tract was suspected. Radiographic and endoscopic examinations revealed a pedunculate mass on the dorsal aspect of the rhinopharynx, which was removed with endoscopically assisted electrosurgery. Histologic examination revealed a chronic pyogranulomatous inflammation with eosinophilic club-like bodies surrounding small colonies of rod-shaped bacteria. Results of histochemical staining were consistent with Actinobacillus-like bacteria and a diagnosis of respiratory actinobacillosis was reached. Surgery and antibiotic therapy were resolutive, as demonstated by an endoscopic check at the second month after surgery, even without the association of the traditional iodine cure, which is regarded as the treatment of choice for actinobacillosis.

Atividade hemolítica de Actinobacillus actinpmycetemcomitans

Quarenta e uma amostras de A. actinomycetemcomitans, 4 ambientais e 37 humanas isoladas e caracterizadas no laboratório de Microbiologia Oral e Anaeróbios do Departamento de Microbiologia do ICB/UFMG, foram testadas quanto à capacidade hemolígica utilizando-se sangue de carneiro e humano. Foi caracterizada hemólise parcial em 34 dos 41 isolados. Destes somente 8 amostras humanas produziram hemólise em ambos os tipos de sangue, isoladas de indivíduos com doença periodontal (5) e sem doença periodontal (3). Considerando-se a relativa heterogeneidade desse grupo bacteriano, esses resultados suscitam maiores estudos sobre sua atividade hemolígica, visando a uma possível aplicaçäo em termos de sistemática e pagogênese