In the current issue of the American Journal of Kidney Diseases, Agrawal et al report a patient with an interesting presentation of renal sarcoidosis. A kidney biopsy performed for evaluation of acute kidney injury, hypercalcemia, and neurological symptoms revealed numerous noncaseating granulomas and chronic tubulointerstitial nephritis. The unusual finding was that many granulomas involved the small arteries causing a vasculitic injury. The presence of additional cerebral and pulmonary lesions on imaging, careful exclusion of other causes of granulomatous disorders, and the response to glucocorticoids established the diagnosis of sarcoidosis with renal granulomatous interstitial nephritis and vasculitis. The following questions will test your knowledge of sarcoidosis and kidney disease.

1. The most common renal manifestation of sarcoidosis is:

a. Hypercalciuria
b. Hypercalcemia
c. Tubulointerstitial nephritis
d. Vasculitis
e. Glomerulonephritis
f. Nephrolithiasis

2. What is the role of measuring serum angiotensin converting enzyme (ACE) level in sarcoidosis?

a. ACE level has a high specificity (i.e. a negative result rules out sarcoidosis).
b. ACE level is helpful in monitoring response to therapy.
c. Elevated ACE level is not pathognomonic of sarcoidosis.
d. Elevated ACE level predict recurrence after kidney transplantation.

3. Renal sarcoidosis is best diagnosed by:

a. Gallium scan
b. PET scan
c. Ultrasound
d. Kidney biopsy

4. Interaction between environmental agents and genetic factors is thought to lead to the development of sarcoidosis. Genetic material of which bacteria has been found in the
granulomas in sarcoidosis?

a. Pneumocystis jiroveci
b. Propionibacterium acnes
c. Pseudomonas aeroginosa
d. Pasturella multocida
e. Peptostreptococcus

Post by Dr. Varun Agrawal (author of the article) and Dr. Kenar Jhaveri

To see the answers, please click here.

To view the abstract or full-text (subscription required), please visit AJKD.org.