Is Itching a Symptom of Hemophagocytic Lymphohistiocytosis?
No, itching (pruritus) is not a recognized presenting symptom of hemophagocytic lymphohistiocytosis (HLH). Skin manifestations in HLH occur in up to 65% of patients, but these present as visible rashes rather than pruritus.
Documented Cutaneous Manifestations of HLH
The skin findings in HLH are morphologically distinct and do not typically include pruritus as a primary complaint:
Skin rash is listed among presenting symptoms in the 2021 ASCO guidelines for CAR T-cell therapy-related HLH, but this refers to visible eruptions rather than itching 1
Specific cutaneous presentations include:
- Erythroderma (generalized redness) 2
- Generalized purpuric macules and papules (purple spots from bleeding into skin) 2
- Morbilliform eruptions (measles-like rash) 2, 3
- Pyoderma gangrenosum 3
- Panniculitis (inflammation of subcutaneous fat) 3
- Stevens-Johnson syndrome 3
- Atypical targetoid lesions and bullae 3
Core Presenting Symptoms of HLH
The cardinal features of HLH that should prompt diagnostic consideration are:
- Prolonged high fever (often >39.4°C) - one of the most consistent features 4, 5
- Hepatosplenomegaly (enlarged liver and spleen) 1, 4
- Cytopenias affecting two or more cell lines 4
- Hyperferritinemia (ferritin ≥500 μg/L, often >10,000 ng/mL) 1, 6
Additional systemic symptoms include:
- Swollen lymph nodes 1
- Jaundice 1
- Respiratory problems (coughing, trouble breathing) 1
- Gastrointestinal symptoms (stomach ache, vomiting, diarrhea) 1
- Neurological problems (headaches, trouble walking, vision disturbances, weakness) 1
Clinical Pitfall to Avoid
Do not dismiss HLH because a patient lacks pruritus. The cutaneous findings in HLH are primarily visible eruptions that may be identified on physical examination rather than symptomatic itching 2, 3. The histologic findings of skin lesions in HLH are typically non-specific and represent a diagnosis of exclusion 3. Awareness of the varied cutaneous manifestations can assist in initial diagnosis and potentially signify disease recurrence 2.