Hooo-Hooo Hooo-Hooo Volume 11 Nr 4 - Page 17

such scenarios occur in springbok, but they would be considered likely. Following innoculation of the virus there is a viremic phase with skin nodules usually developing around 28 days later. Skin nodules usually appear within 48 hours of the febrile reaction. Clinical Signs and Pathology Cutaneous nodules, lymphadenopathy and pyrexia are the lesions most commonly described in springbok. The cutaneous lesions are firm, circumscribed, nodules ± 0.5-5.0 cm in diameter with lesion distribution being similar to that described in cattle namely head, neck, limbs, other, genitalia and perineum (figure 1 and figure 2). Nodules affecting the scrotum, perineum, udder, vulva, glans penis, eyelids, and conjunctiva are usually flatter (figure 2 arrow). Typically, nodules undergo necrosis and sequestration, but some may resolve rapidly and completely, while a few may become indurated and persist as hard intradermal lumps for many months. There is a high risk of secondary bacterial infection during the period of necrosis and sequestration. Figure 2: Springbok – Lumpy skin disease demonstrating nodules on the eyelids have a faller appearance (arrow). (Courtesy Dr Martin Malan) Diagnosis Collection of skin biopsies into 10% buffered formalin for histopathology and subsequent immunohistochemistry forms the basis of disease diagnosis. Immunohistochemistry (IHC) for LSDV is a rapid, specific and sensitive procedure for disease diagnosis, as it enables demonstration of the virus within the histological lesions allowing for confident confirmation of clinically disease. Polymerase chain reaction (PCR) has largely replaced virus isolation as a diagnostic procedure for detection of the virus. The preferred samples for PCR analysis include fresh skin nodules, scabs or dried swabs thereof, as these tissues carry high concentrations of virus. The PCR analysis is also effective on saliva and nasal secretions (dry swabs) as well as blood collected into EDTA. Figure 1: Springbok – Lumpy skin disease with cutaneous nodules over the face, neck and trunk.(Courtesy Dr Martin Malan) Histological examination of H&E stained sections enables detection of the characteristic pathology of ballooning epidermal degeneration, follicular epithelial hyperplasia, deep dermal thrombosis 2017 December 17