CONSULT ROUNDS: Hemophagocytic syndrome and the kidney?

What is hemophagocytic syndrome? and what do nephrologists have to do with it?

Its a dysregulation and  inappropriate activation of the immune system.  Its infiltration of non malignant macrophages and phagocytosis of blood cells. 
Key features: fevers, hepatosplenomegaly, pancytopenia, low fibrinogen levels, LFTS dysfunction, seizures, hypertriglyceridemia. and multi organ failure with AKI

Primary cause: immune dysregulation
Secondary causes: autoimmune such as Stills disease, SLE.  Infections such as EBV. Herpes, PB19, HIV.etc and malignancy such as T and B leukemias/lymphomas. 

Renal manifestations:

ATN and interstitial disease( being most common on autopsy findings), macrophage infiltration, intra renal hemaphagocytosis
Collapsing FSGS( most common glomerular disease), MCD, FSGS 
TMA, and intravascular lymphoma

Treatment:

Chemotherapy usually etoposide based
IVIG
Rituximab

EBV disease- think this syndrome as well if above features are present.

What do nephrologists have to do with it?- recognize it when appropriate as AKI and proteinuria is not uncommon with this entity. 


References:
http://www.ncbi.nlm.nih.gov/pubmed/12813287
http://211.144.68.84:9998/91keshi/Public/File/19/5-6/pdf/nrneph.2009.73.pdf
http://www.ncbi.nlm.nih.gov/pubmed/16557222