| In April 2001, a 4-month-old pig died with severe dermal and subcutaneous
hemorrhage at a farm in Tokushima prefecture in Japan. At necropsy, the
pig had skin lesions that were most striking: dark red, flat and varying
in size from small irregular areas less than 1 cm in diameter to widespread
contiguous lesions over the limbs, particularly in the inguinal area. The
kidney was markedly enlarged and pale, with surface and cut-surface petechiation.
Microscopically, there was glomerulonephritis with hemorrhage and fibrin
deposition in the Bowman's capsule. Mild to moderate mesangial proliferation
was seen in the oppressed glomeruli. Renal tubules were distended with
a protein cast in the lumen. Protein reabsorption droplets were widespread.
Mild to moderate fibrosis and non-suppurative infiltration were observed
in the intersitial tissue. In the skin, there was necrosis, hemorrhage
and suppurative inflammation in the epidermis through the middle layer
of the dermis, with necrotising vasculitis involving medium-sized or small
arterial branches. Vasculitis was also seen in the spleen, esophagus, stomach
and colon. The macroscopic and microscopic findings were identical to those
described in previous articles on porcine dermatitis and nephropathy syndrome
(PDNS). This is the first report of PDNS in Japan. (Infectious Disease
Pathology Section, Department of Infectious diseases TEL +81-29-838-7837) |