Chronic histiocytic intervillositis in consecutive miscarriages: A potential pitfall in routine examination of conceptus

INTRODUCTION: Chronic histiocytic intervillositis (CHI) is a rare placental lesion strongly associated with recurrent miscarriages and fetal losses. It requires histopathological diagnosis and can only be made after delivery of the products of conception (POC). We describe a case of CHI in a 41-yearold lady with a 16-year history of thirteen recurrent consecutive first trimester miscarriages.

CASE REPORT: The patient is a 41-year-old lady who suffered first trimester miscarriages in all her thirteen pregnancies. The relevant clinical investigations revealed neither significant nor helpful findings in determining the cause of recurrent miscarriages. Histological findings in each except one of the submitted conceptual tissue showed similar features of histiocytic aggregates primarily within the intervillous spaces, a characteristic description of CHI. One of the samples showed degenerative changes.

DISCUSSION: Practicing pathologists are not familiar with the histological features of CHI and this may be a potential pitfall in routine examination of POCs. Recognising this entity allows for accurate diagnosis and hence better management. The aetiology remains unclear, although an immunopathological basis are being explored.