Granulomatous herpes simplex encephalitis in an infant with multicystic encephalopathy: a distinct clinicopathologic entity?

BACKGROUND: Herpes simplex virus encephalitis can manifest as a range of clinical presentations including classic adult, neonatal, and biphasic chronic-granulomatous herpes encephalitis. METHOD: We report an infant with granulomatous herpes simplex virus type 2 encephalitis with a subacute course and multicystic encephalopathy. CASE: A 2-month-old girl presented with lethargy and hypothermia. Computed tomography scan of the head showed multicystic encephalopathy and calcifications. Cerebrospinal fluid analysis by polymerase chain reaction testing for herpes simplex virus 1 and 2, enterovirus, and cytomegalovirus was negative. Normal cerebrospinal fluid interferon-α levels argued against Aicardi-Goutières syndrome. The patient died 2 weeks after presentation. At autopsy, multicystic encephalopathy was confirmed with bilateral gliosis, granulomatous inflammation with multinucleated giant cells, and calcifications. Bilateral healing necrotizing retinitis suggested a viral etiology, but retina and brain were free of viral inclusions and immunohistochemically negative for herpes simplex virus-2 and cytomegalovirus. However, polymerase chain reaction analysis showed herpes simplex virus-2 DNA in four cerebral paraffin blocks. Subsequent repeat testing of the initial cerebrospinal fluid sample using a different polymerase chain reaction assay was weakly positive for herpes simplex virus-2 DNA. CONCLUSION: Granulomatous herpes simplex virus encephalitis in infants can present with subacute course and result in multicystic encephalopathy with mineralization and minimal cerebrospinal fluid herpes simplex virus DNA load. Infectious etiologies should be carefully investigated in the differential diagnosis of multicystic encephalopathy with mineralization, in particular if multinucleated giant cells are present.

Superficial leiomyosarcoma: a clinicopathologic review and update.

BACKGROUND: Superficial leiomyosarcomas (SLMSs) are rare soft tissue malignancies. A clinicopathologic review of 25 cases was undertaken. METHODS: Twenty-five cases diagnosed between 1990 and 2007 were reviewed. Clinical information was obtained from patient charts. Histologic slides were reviewed, and immunohistochemical stains were performed. RESULTS: All patients presented with a nodule. Fourteen tumors were confined to the dermis and 11 involved subcutaneous tissue. Smooth muscle markers were positive in all cases. CD117 was consistently negative. Novel histological features included epidermal hyperplasia, sclerotic collagen bands and increasing tumor grade with the depth of the lesion. Poor outcome was associated with size > 2 cm, high grade and depth of the lesion. CONCLUSIONS: SLMSs are rare but important smooth muscle tumors of the skin. The clinical presentation may be non-specific. The histologic appearance is that of a smooth muscle lesion, but epidermal hyperplasia and thickened collagen bands are previously underrecognized features. Immunohistochemical stains are useful in confirming smooth muscle differentiation, but CD117 is of limited utility. SLMS can appear low grade or even benign on superficial biopsies, leading to undergrading or a delay in the correct diagnosis. Clinicians and pathologists alike should therefore be aware of these pitfalls and must approach these cases with caution.