CRP-35

CRP-35

Clinical History

The patient is a 25 year old female who is status post renal transplant two years ago. She presents for explant nephrectomy due to rejection.

Gross Description

The specimen is received in a container labeled with the patient's name, medical record number and “transplant nephrectomy”. Received in saline solution is a fragmented and distorted nephrectomy specimen that weighs in aggregate 250 grams and measures 15 x 8 x 4 cm in greatest dimension. The kidney is externally covered by a tan-pink shiny capsule with areas of petechial hemorrhages. This capsule strips with ease, revealing a red-brown granular external surface. The cut surface is pale tan with congestion. The cortico-medullary junction cannot be grossly identified and the portion of pelvico-calyceal system that can be grossly identified, is lined by a tan-white smooth glistening and congested mucosa. No gross lesions are present. The specimen is submitted in four cassettes.

Pathology

Case CRP-035 IHC_control

Microscopic Description, Immunofluorescence, and Electron Microscopy.

Microscopic Description

Light Microscopy

A1-A4 – Sections through transplant kidney. A microscopic examination has been performed.

Immunofluorescence

IHC-CD68

Diagnosis and Comments

Kidney, transplant nephrectomy – Malakoplakia - Moderately severe chronic vascular rejection and acute vascular rejection - Acute tubulitis. - Tubular atrophy and interstitial fibrosis

Much of the renal parenchyma is replaced by sheets of large eosinophilic macrophages with occasional small round structures in their cytoplasm, consistent with Michaelis-Guttman bodies. These macrophages stain strongly with CD68 and are negative for cytokeratin. The stains for fungal organisms, acid fast bacilli and Whipples bacteria are negative.

Acid fast bacilli are not easily decolorized by acid during staining. This is characteristic of mycobacteria.