Hematologic complications of HIV infection
HIV infection produces cytopenias, coagulation abnormalities, and B-cell lymphomas through mechanisms that shift with CD4 count, from immune-mediated peripheral destruction and drug toxicity at higher CD4 counts to opportunistic marrow infiltration and aggressive lymphoma once CD4 falls below 100-50/mcL. Antiretroviral therapy is the single most effective intervention across nearly all of these complications, and management otherwise follows the specific cytopenia or malignancy identified after excluding drug causes, nutritional deficiency, and coinfection.
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What this article covers
- Overview
HIV affects every blood lineage, and the dominant mechanism shifts with CD4 count: immune-mediated destruction and drug toxicity predominate at preserved CD4 counts, while opportunistic marrow…
- Epidemiology
Isolated thrombocytopenia occurs in 5-10% of patients with chronic HIV infection, independent of viral load or CD4 count, so it can appear even in a well-controlled patient.
- Risk factors
CD4 count below 200/mcL, and especially below 50/mcL: the strongest driver of cytopenia severity and the shift toward marrow infiltration and aggressive lymphoma.
- Pathophysiology
Chronic immune activation drives anemia of chronic disease through cytokine-mediated hepcidin induction that sequesters iron and blunts erythropoiesis, as in anemia of chronic disease.
- Clinical features
Mucocutaneous bleeding from thrombocytopenia is often the earliest sign: petechiae, easy bruising, gum bleeding, or epistaxis, sometimes preceding the HIV diagnosis itself.
- Differential diagnosis
Thrombotic thrombocytopenic purpura: schistocytes, severe ADAMTS13 deficiency, and neurologic findings distinguish it from isolated HIV-associated thrombocytopenia; HIV itself is a recognized trigger.
- Diagnosis
No single test diagnoses "hematologic complications of HIV" as one entity: each complication is confirmed by demonstrating the abnormality (a cytopenia on CBC, a coagulation abnormality, or…
- Management
Start or optimize antiretroviral therapy in every patient, regardless of the specific cytopenia or CD4 count: immune reconstitution is the most broadly effective intervention; a preferred regimen is…
- Complications
Life-threatening bleeding from severe thrombocytopenia without prompt treatment.
- Prognosis
Antiretroviral therapy is the dominant prognostic factor across every category: viral suppression and CD4 recovery correct most cytopenias and improve chemotherapy tolerance.
- Prevention
Start ART for every person diagnosed with HIV regardless of CD4 count: immune reconstitution is the single most effective measure to prevent HIV-driven cytopenias and lymphoma (see acute HIV infection for rapid-start principles).
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Related articles
- Acute HIV infection
Acute HIV infection, also called the acute retroviral syndrome, is the symptomatic viremic phase in the days to weeks after HIV acquisition, presenting with fever, fatigue, myalgia, rash, and pharyngitis at a time when antibody testing may still be negative. Diagnosis requires an HIV RNA viral load, and antiretroviral therapy should begin as soon as the patient is ready, regardless of CD4 count.
- HIV antiretroviral therapy (ART)
Antiretroviral therapy (ART) combines three or more drugs from at least two classes to suppress HIV replication. First-line therapy is bictegravir/emtricitabine/tenofovir alafenamide or dolutegravir-based triple therapy, started as soon as the patient is ready regardless of CD4 count, and continued for life to prevent AIDS and transmission.
- Anemia of chronic disease
Anemia of chronic disease, also called anemia of inflammation, is a normocytic normochromic anemia driven by hepcidin-mediated iron sequestration and cytokine blunting of erythropoiesis in patients with chronic infection, autoimmune disease, malignancy, or kidney disease. The iron-study pattern of low serum iron, low total iron-binding capacity, and normal-to-high ferritin distinguishes it from iron deficiency, and management centers on treating the underlying disease rather than iron supplementation.
- Neutropenia
Neutropenia is a reduced absolute neutrophil count that raises infection risk sharply once the count falls below 500/microL, most often from chemotherapy or another marrow-suppressing or idiosyncratic drug. Diagnosis rests on a repeat CBC with differential and smear review followed by a directed search for cause, and management centers on stopping the offending agent, treating any underlying disease, and using G-CSF and neutropenic precautions when the count is low or the patient is febrile.
- Immune thrombocytopenia (ITP)
Immune thrombocytopenia is an acquired isolated thrombocytopenia from antiplatelet autoantibody-mediated destruction plus impaired marrow production, presenting with mucocutaneous bleeding and no splenomegaly. It is a diagnosis of exclusion made by a normal smear and normal other cell lines, and treatment is driven by bleeding risk, starting with glucocorticoids with or without IVIG or anti-D.
- Thrombotic thrombocytopenic purpura (TTP)
Thrombotic thrombocytopenic purpura is a thrombotic microangiopathy caused by severe ADAMTS13 deficiency that lets ultralarge von Willebrand factor multimers drive platelet microthrombi; the key dyad of microangiopathic hemolytic anemia plus thrombocytopenia without another cause mandates the PLASMIC score, an ADAMTS13 activity and inhibitor level, and emergent plasma exchange started before results return.
- Non-Hodgkin lymphoma
Non-Hodgkin lymphoma is a heterogeneous group of B-cell (about 85%) and T-cell lymphoid malignancies that spread noncontiguously and often involve extranodal sites, ranging from indolent follicular lymphoma to aggressive diffuse large B-cell lymphoma to highly aggressive Burkitt lymphoma. Diagnosis requires excisional or core biopsy with flow cytometry and cytogenetics, Ann Arbor staging with PET-CT, and treatment is subtype-specific, from observation to R-CHOP to intensive Burkitt regimens with aggressive tumor lysis and CNS prophylaxis.
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Kaposi sarcoma is a human herpesvirus 8-associated vascular malignancy that presents as violaceous macules, papules, plaques, or tumors of the skin, mouth, gastrointestinal tract, or lungs, most often in HIV-associated, transplant-related, or classic elderly disease. Diagnosis is confirmed by biopsy. Every patient with HIV-associated Kaposi sarcoma starts or optimizes antiretroviral therapy, with liposomal doxorubicin 20 mg/m2 intravenously every 21 days added for extensive or visceral disease.