RESUMO
BACKGROUND AND AIMS: Rhabdomyolysis occurs due to injury to skeletal muscle fibers and the release of muscle constituents into the circulation. Myoglobin cast nephropathy leading to acute kidney injury is one of the most severe complications of rhabdomyolysis. This is a retrospective study which aims to analyse the clinicopathological features of myoglobin cast nephropathy. METHODS: A total of 57 cases of myoglobin cast nephropathy were identified after performing immunohistochemical staining for myoglobin on all renal biopsies with pigment casts. The clinical, laboratory data, histopathological findings and clinical outcome of these cases were evaluated. RESULTS: The mean patient age was 34.47 years (range 17-77) and the male to female ratio was 6.1:1. All patients presented with acute kidney injury with mean serum creatinine of 8.4 mg/dl (range: 1.7 to 20.8 mg/dl). Rhabdomyolysis was clinically suspected only in 31 patients. Along with myoglobin casts, acute tubular injury was present in all the biopsies. The most frequent conditions associated with myoglobin cast nephropathy in our study were snake envenomation and unaccustomed physical activities. A few activities that caused rhabdomyolysis in our patients were unique to India. CONCLUSION: Clinicians should be aware of the wide spectrum of causes for rhabdomyolysis. The classical clinical and laboratory findings of rhabdomyolysis may not be present in many of the patients. The pathologist must have a high index of suspicion, and immunohistochemical stain should be used to confirm the diagnosis.
RESUMO
Atheroembolic renal disease (AERD), a part of systemic cholesterol embolization syndrome, is caused by the occlusion of small arteries in the kidneys by cholesterol crystal emboli from ulcerated atherosclerotic plaques. Kidney is commonly involved because of its proximity to the abdominal aorta and its enormous blood supply. AERD is an under diagnosed condition. We report eight cases of AERD, highlighting the variability in its clinical presentation and the importance of a renal biopsy to arrive at a definitive diagnosis.
RESUMO
Renal cell carcinomas (RCCs) with t(6,11) are very rare tumours. Only a few cases have been reported so far. t(6,11) results in fusion of alpha gene and transcription factor EB (TFEB) gene resulting in the overexpression of TFEB. The specific light and immunohistochemical features help in the diagnosis of this rare type of tumor. We report a case of t(6,11) RCC in a 38-year-old female who was incidentally found to have a right renal mass. We present this case to emphasize the typical light microscopic picture of this extremely rare tumor. Two population of cells are seen: larger cells with abundant cytoplasm and smaller cells with scant cytoplasm. Smaller cells are arranged around hyaline nodules resulting in the formation of characteristic pseudorosettes. Immunohistochemically, these tumors are diffusely positive for vimentin and focally positive for HMB 45 and CD 117. Knowledge about the typical biphasic light microscopic appearance and the characteristic immunohistochemical features help in the diagnosis of this rare type of translocation associated RCC.
