Karyomegalic interstitial nephritis, a fascinating histopathologic entity for pathologists: Be watchful of the FAN1 gene mutations.

ABSTRACT: Karyomegalic interstitial nephritis (KIN) is an uncommon autosomal recessive disease, which is characterized by enlarged and hyperchromatic nuclei of the renal tubular epithelial cells. It is associated with mutations in Fanconi anemia-associated nuclease 1 gene, which is responsible for DNA repair, and these pathogenic mutations are responsible for progressive renal failure in young adults. We present a case of a 29-year-old female with end-stage renal disease who had a family history of early-onset renal failure in two of the siblings. Her elder sister with chronic kidney disease stage III was advised to be biopsied to look for any familial causes. Stained sections of renal biopsy revealed normal glomeruli. Tubular epithelial cells showed nuclear changes focally like hyperchromasia, karyomegaly, and anisonucleosis. On direct immunofluorescence, all glomeruli were negative for deposits with all antisera. Based on these findings, a final opinion of KIN was given.

Strongyloides stercoralis infection masquerading as malignant ascites in a case of angiosarcoma.

ABSTRACT: Strongyloides stercoralis is a parasitic nematode that infects millions of people worldwide. It primarily infects humans but can also be found in domestic animals and primates. The severity of infection varies from asymptomatic to life-threatening complications. We present a case of a 56-year-old male with a known case of angiosarcoma liver with massive ascites and low-grade fever. He was clinically diagnosed as having malignant ascites and was planned for chemotherapy. During therapeutic cum diagnostic ascitic tap, cell block sections revealed the presence of cross sections of nematode S. stercoralis gravid uterus with eggs. Later, stool for ova and cysts also revealed multiple larval forms of the nematode. S. stercoralis hyperinfection is often accompanied by sepsis or meningitis with enteric organisms. Patient was started on tab. ivermectin 12 mg once a day for two days (in the standard dosage of 200 mcg/kg) was then repeated in the same dosage for another two days after two weeks, and gradually the ascites settled. Post-treatment ascitic tap cell block preparations did not show any parasites. Patient has been on follow-up for 6 months, and he remains asymptomatic.