Suppurative meningoencephalitis and perineuritis caused by Streptococcus gallolyticus in a Japanese Black calf

Abstract

A 179-day-old calf, which was weak and stunted, showed neurological signs and was euthanized. Postmortem examination revealed extensive and severe cloudy area in the meninges, and pleural pneumonia. Gram-positive cocci were isolated from systemic organs. Biochemical and 16S rRNA gene sequence analyses identified the isolate as Streptococcus gallolyticus, and its subspecies was suggested to be gallolyticus (SGG). The isolate was classified as a novel sequence type (ST115) by the multilocus sequence typing scheme for SGG and showed susceptibility to penicillin, ampicillin, amoxicillin, florfenicol, sulfamethoxazole-trimethoprim, and chloramphenicol. Histopathologically, suppurative meningoencephalitis and perineuritis were detected. As SGG has been isolated solely from a cow with mastitis in Japan, this is the first SGG infection in a calf with suppurative meningoencephalitis and perineuritis in this country.

Keywords: Multilocus sequence typing; Streptococcus gallolyticus subsp. gallolyticus; calf; perineuritis; suppurative meningoencephalitis.

Fig. 1.

a. At necropsy, a 179-day-old calf was very small and thin similar to 120-day-old calf. The buttock and limbs were covered with watery feces. b. Extensive and severe cloudy areas in the meninges were detected on the brain surface. c. Fibrously thickened pulmonary pleura in the right anterior lung lobe (arrowheads). d. Perivascular cuffing of neutrophils and macrophages in the cerebral parenchyma. Hematoxylin and eosin (H&E) staining. Bar=20 μm. e. Infiltration of neutrophils and macrophages in the temporal lobe meninges of the cerebrum. H&E staining. Bar=50 μm. f. Infiltration of neutrophils and macrophages around the spinal cord. H&E staining. Bar=20 μm. g. Gram-positive cocci phagocytosed by macrophages in lesions of cerebrum (arrowheads). Gram staining. Bar=20 μm. h. Positive reactions of Gram-positive cocci to anti Streptococcus group D serum antibody were found in lesions of the cerebrum. Immunohistochemical staining. Bar=20 μm.