HLH and Infection
Case reports and case series on the association of infections and HLH are summarized at URL: https://www.cdc.gov/ncidod/eid/vol6no6/fisman_refs.htm
Disseminated infection with an unusual organism in a patient with HLH may represent secondary infection in an immunocompromised host; however, the resolution of HLH following treatment of infection suggests that, in many cases, HLH is secondary to the underlying infection.
A diagnosis that takes into account all the underlying diseases associated with HLH would not be practical, and formal guidelines for evaluating patients with suspected infection-associated HLH have not been established. Nevertheless, all patients meeting the criteria for HLH should undergo initial diagnostic tests that include routine cultures of blood and urine and chest radiography to screen for such infections as miliary tuberculosis. Attempts should be made to screen for infection with EBV, CMV, and parvovirus B19, either through serologic testing or polymerase chain reaction, in-situ hybridization, or (in the case of CMV) immunofluorescent antigen testing. Serologic testing for HIV and human herpesvirus-6 infection should also be considered, and throat and rectal swabs should be taken for viral culture. Because of the association between HLH and fungal infections, lysis-centrifugation blood cultures and fungal antigen testing should be considered for all patients with HLH. Even if an infection known to be associated with HLH has been confirmed, cell marker and T-cell receptor gene rearrangement tests should be performed on bone marrow or other tissue specimens to determine whether an underlying T-cell lymphoma is present.
Extensive testing for underlying infecting organisms should be guided by epidemiologic data and the patient's medical history. For example, in a patient with underlying HIV infection, HLH has been associated with infections that commonly affect patients with AIDS (e.g., pneumococcal disease, pneumocystosis, histoplasmosis, and infection with Penicillium marneffei) and with T-cell lymphoma. Patients with a history of travel or animal exposure should be screened for such infections as leishmaniasis, brucellosis, rickettsioses, and malaria. In bone marrow transplant patients, attempts should be made to isolate adenovirus from urine, nasopharyngeal and rectal swabs, and tissue specimens.
Because so many immunologic, neoplastic, genetic, and infectious disorders may be associated with HLH, clinicians should work closely with pathologists and microbiologists to clearly define precipitating or underlying illnesses.
Emerging Infectious Diseases. 2000;6(6) © 2000 Centers for Disease Control and Prevention (CDC)
Cite this: Hemophagocytic Syndromes and Infection - Medscape - Nov 01, 2000.