[Pathology of enterovirus 71 infection: an autopsy study of 5 cases].
OBJECTIVE
To study the clinicopathologic features of fatal enterovirus 71 (EV71) infection.


METHODS
Autopsy was performed in 5 neonates died of EV71 infection. Tissue samples from major organs were collected, formalin-fixed and examined under light microscopy. Immunohistochemical study was carried out in selected examples.


RESULTS
Four of the 5 cases showed predominant changes in central nervous system, with encephalitis and encephalomyelitis identified mainly in brainstem and upper cervical spinal cord. Histologic findings included neuronal degeneration and necrosis, neuronophagia, perivascular cuffing and diffuse or nodular hyperplasia of macrophages/microglia. Cerebral edema, brain herniation and aseptic meningitis were also noted. The lungs showed mainly pulmonary congestion, neurogenic pulmonary edema and focal hemorrhage. There were minimal changes in the intestinal epithelium. The intestinal lymphoid tissue however was hyperplastic and associated with apoptosis of follicular center cells. The remaining case had cerebral edema and mild meningitis. The lung alveolar septa were thickened with lymphocytic infiltrates. Some alveolar cells were hyperplastic and associated with diffuse hyaline membrane formation. No specific abnormalities were identified in gastrointestinal tract. In all the 5 cases studied, there was enlargement of lung hilar and mesenteric lymph nodes, coupled with apoptosis of follicular center cells. In general, no significant pathologic changes were demonstrated in heart, liver and kidneys.


CONCLUSIONS
In fatal EV71 infection, the major pathologic changes lie in the central nervous system. The pulmonary lesions are mainly secondary in nature. The usual cause of death is cerebral edema complicated by brain herniation and pulmonary edema. It is also noteworthy that some cases show only lung damages, without classic neurologic changes.
Lu
Min
M
Department of Pathology, School of Basic Medical Sciences, Peking University, Beijing 100083, China.
Meng
Gang
G
He
Yao-xin
YX
Zheng
Jie
J
Liao
Song-lin
SL
Zhong
Yan-feng
YF
Zhao
Xi-shun
XS
Shao
Hong-quan
HQ
Wang
Yu-ping
YP
Gao
Zhan-cheng
ZC
Gao
Zi-fen
ZF
D001344:Autopsy; D001929:Brain Edema / Q000209:etiology / Q000473:pathology*; D001933:Brain Stem / Q000473:pathology*; D002675:Child, Preschool; D018792:Encephalitis, Viral / Q000209:etiology / Q000473:pathology; D004679:Encephalomyelitis / Q000209:etiology / Q000473:pathology; D029821:Enterovirus A, Human / Q000302:isolation & purification*; D004769:Enterovirus Infections / Q000150:complications / Q000473:pathology* / Q000821:virology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011654:Pulmonary Edema / Q000209:etiology / Q000473:pathology*; D013116:Spinal Cord / Q000473:pathology