- Hemophagocytic lymphohistiocytosis
Name = PAGENAME
Caption = Light microscopic image of
bone marrowshowing stromal macrophages containing numerous red blood cellsin their cytoplasm
DiseasesDB = 31418
ICD10 = ICD10|D|76|1|d|70
ICD9 = ICD9|288.4
OMIM = 267700
OMIM_mult = OMIM2|603553 OMIM2|608898 OMIM2|603552 | MedlinePlus =
eMedicineSubj = ped
eMedicineTopic = 745
MeshID = D051359
Hemophagocytic lymphohistiocytosis (HLH) is an unusual syndrome characterized by
fever, splenomegaly, jaundice, and the pathologic finding of hemophagocytosis. Lymphocytosisand histiocytosisare also part of the presentation. [MeshName|Lymphohistiocytosis,+Hemophagocytic]
HLH may be associated with malignant, genetic, infectious, or autoimmune diseases.
cytokines, including interferon-g and tumor necrosis factor-a, by EBV-infected T lymphocytesmay play a role in the pathogenesis of HLH. EBV-associated HLH may mimic T-cell lymphomaand is treated with cytotoxic chemotherapy. In contrast, hemophagocytic syndromes associated with nonviral pathogens often respond to treatment of the underlying infection.
HLH comprises familial (primary) hemophagocytic lymphohistiocytosis (FHL) and secondary HLH (SHLH), both clinically characterized by the features described above, in particular fever,
hepatosplenomegaly, and cytopenia.
Familial (primary) forms
autosomal recessivedisorder, is invariably fatal when untreated. It is associated with defective triggering of apoptosisand reduced cytotoxic activity, resulting in a widespread accumulation of T lymphocytes and activated macrophages.
single nucleotide polymorphisms increase risk of HLH.cite journal |author=Donn R, Ellison S, Lamb R, Day T, Baildam E, Ramanan AV |title=Genetic loci contributing to hemophagocytic lymphohistiocytosis do not confer susceptibility to systemic-onset juvenile idiopathic arthritis |journal=Arthritis Rheum. |volume=58 |issue=3 |pages=869–74 |year=2008 |month=March |pmid=18311812 |doi=10.1002/art.23270 |url=http://dx.doi.org/10.1002/art.23270]
There are four types,cite web |url=http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=hlh |title=Hemophagocytic Lymphohistiocytosis, Familial -- GeneReviews -- NCBI Bookshelf |format= |work= |accessdate=] and each is associated with a specific gene:
* FHL1 -
* FHL2 -
* FHL3 -
* FHL4 -
HLF is also prominently linked with
Epstein-Barr virus(EBV) infection, [cite journal |author=Fisman DN |title=Hemophagocytic syndromes and infection |journal=Emerging Infect. Dis. |volume=6 |issue=6 |pages=601–608 |year=2000 |pmid=11076718 |doi= |url=http://www.cdc.gov/ncidod/eid/vol6no6/fisman.htm] however it can also be associated with other viruses as well as fungal infections.
Etoposide, cyclosporin, and methotrexateare among the medications that have been proposed. [cite journal |author=Henter JI, Samuelsson-Horne A, Aricò M, "et al" |title=Treatment of hemophagocytic lymphohistiocytosis with HLH-94 immunochemotherapy and bone marrow transplantation |journal=Blood |volume=100 |issue=7 |pages=2367–2373 |year=2002 |pmid=12239144 |doi=10.1182/blood-2002-01-0172 |url=http://www.bloodjournal.org/cgi/pmidlookup?view=long&pmid=12239144]
Use of the
CHOPprotocol has been described.cite journal |author=Shin HJ, Chung JS, Lee JJ, "et al" |title=Treatment outcomes with CHOP chemotherapy in adult patients with hemophagocytic lymphohistiocytosis |journal=J. Korean Med. Sci. |volume=23 |issue=3 |pages=439–44 |year=2008 |month=June |pmid=18583880 |doi=10.3346/jkms.2008.23.3.439 |url=http://jkms.org/contents/jkms.php?pubyear=2008&vol=23&fpage=439]
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