Diagnostic utility of melanin production by fungi: Study on tissue sections and culture smears with Masson-Fontana stain.

Background: Dematiaceous fungi appear brown in tissue section due to melanin in their cell walls. When the brown color is not seen on routine H and E and culture is not available, differentiation of dematiaceous fungi from other fungi is diffi cult on morphology alone. Aims and Objective: To study if melanin production by dematiaceous fungi can help differentiate them from other types of fungi. Materials and Methods: Fifty tissue sections of various fungal infections and 13 smears from cultures of different species of fungi were stained with Masson Fontana stain to assess melanin production. The tissue sections included biopsies from 26 culture-proven fungi and 24 biopsies of fi lamentous fungi diagnosed on morphology alone with no culture confi rmation. Results: All culture-proven dematiaceous fungi and Zygomycetes showed strong positivity in sections and culture smears. Aspergillus sp showed variable positivity and intensity. Cryptococcus neoformans showed strong positivity in tissue sections and culture smears. Tissue sections of septate fi lamentous fungi (9/15), Zygomycetes (4/5), and fungi with both hyphal and yeast morphology (4/4) showed positivity for melanin. The septate fi lamentous fungi negative for melanin were from biopsy samples of fungal sinusitis including both allergic and invasive fungal sinusitis and colonizing fungal balls. Conclusion: Melanin is produced by both dematiaceous and non-dematiaceous fungi. Masson-Fontana stain cannot reliably differentiate dematiaceous fungi from other fi lamentous fungi like Aspergillus sp; however, absence of melanin in the hyphae may be used to rule out dematiaceous fungi from other fi lamentous fungi. In the differential diagnosis of yeast fungi, Cryptococcus sp can be differentiated from Candida sp by Masson-Fontana stain in tissue sections.

Clear cell papillary cholangiocarcinoma: A case report with review of literature.

Clear cell papillary cholangiocarcinoma is a rare variant of intrahepatic cholangiocarcinoma with only nine reported cases in the literature. This tumor needs to be differentiated from clear cell variant of hepatocellular carcinoma and other metastatic clear cell carcinomas. This tumor is known to have better prognosis compared to conventional intrahepatic cholangiocarcinoma. Hence, it is important to correctly diagnose this entity and differentiate it from other histologic mimics. We describe clinical, histopathological, and immunohistochemical fi ndings of one such rare case in a 66-year-old gentleman who was incidentally detected to have an intrahepatic tumor at routine ultrasound examination.A review of all the similar cases reported so far in the literature is also provided.

Fulminant Subacute Sclerosing Panencephalitis Presenting with Acute Ataxia and Hemiparesis in a 15-Year-Old Boy

BACKGROUND: Subacute sclerosing panencephalitis (SSPE) is a delayed and fatal manifestation of measles infection. Fulminant SSPE is a rare presentation in which the disease progresses to death over a period of 6 months. The clinical features are atypical and can be misleading. CASE REPORT: We report herein a teenage boy who presented with acute-onset gait ataxia followed by right hemiparesis that evolved over 1 month, with left-hemispheric, delta-range slowing on the electroencephalogram (EEG). Magnetic resonance imaging disclosed multiple white-matter hyperintensities, suggesting a diagnosis of acute disseminated encephalomyelitis. He received intravenous steroids, and within 4 days of hospital admission he developed unilateral slow myoclonic jerks. Repeat EEG revealed Rademecker complexes, pathognomonic of SSPE, and an elevated titer of IgG antimeasles antibodies was detected in his cerebrospinal fluid. The disease progressed rapidly and the patient succumbed within 15 days of hospitalization. The diagnosis of SSPE was confirmed by autopsy. CONCLUSIONS: This case illustrates the difficulty of recognizing fulminant SSPE when it manifests with asymmetric clinical and EEG abnormalities.

Sodium iodide symporter, estrogen receptor, and progesterone receptor expression in carcinoma breast - An immunohistochemical analysis.

Background: Sodium iodide symporter (NIS), a transporter of iodine is essential for thyroid hormone biosynthesis. It also plays a role in the radioiodine treatment of thyroid cancers. NIS mediated radioiodine transport to breast cancers is under active investigation due to its potential therapeutic utility. Cellular localization and quantification using immunohistochemistry may provide clues for its utility in management of carcinoma breast. Materials and Methods: Human NIS (hNIS) expression was therefore assessed by utilizing a rabbit polyclonal antibody raised against a cloned hNIS in different grades of infiltrating duct carcinoma of breast and its metastatic deposits namely in lymph nodes, bone marrow, and endometrium. Further, hNIS expression was compared with prognostic markers namely estrogen receptor (ER) and progesterone receptor (PR). Results: hNIS was positive in 90.6% cases (29/32) and Scarff-Bloom-Richardson grading was done in 25 cases and 23 cases were NIS positive. Among nongraded cases, 2/2 cases of carcinoma in-situ were positive and 4/5 were positive in cases having post therapy residual tumor status. The strong positivity for hNIS was seen irrespective of ER or PR status and of grade of breast carcinoma and correlated well with western blot analysis. In all the three metastatic sites, NIS was positive in the tumor. Conclusion: These findings indicate the utility of immnohistochemistry for NIS as a new potential prognostic marker and may provide guidance for possible radio iodine therapy in breast cancer patients.

Utility of dystrophin and utrophin staining in childhood muscular dystrophy.

To determine the utility of dystrophin and utrophin staining in the differential diagnosis of childhood muscular dystrophy. Fifty muscle biopsies of histologically confirmed cases of childhood muscular dystrophy, below 16 years of age, were stained immunohistochemically for dystrophin and utrophin. All the 30 muscle biopsies of patients with Duchenne muscular dystrophy (DMD) showed all or majority of muscle fibers deficient for dystrophin and positive for utrophin. In the 4 female DMD carriers there was mosaic pattern of staining for dystrophin and reciprocal positivity for utrophin. All the muscle biopsies of patients with other childhood onset muscular dystrophies were positive for dystrophin and negative for utrophin. This study shows that dystrophin staining differentiates DMD and DMD carriers from other childhood muscular dystrophies and utrophin staining is of no added value. Utrophin up-regulation may compensate for structural deficiency in dystrophic muscle.