Sickle cell disease complications
Sickle cell disease produces a set of acute crises, vaso-occlusive pain, acute chest syndrome, aplastic crisis, and splenic sequestration, plus chronic end-organ damage, that each demand a distinct recognition pattern and treatment. Acute chest syndrome is the leading cause of death and any fever is a functional-asplenia emergency requiring immediate empiric antibiotics.
- Topic reviewThe full article, organized the way the exam asks it.
- ABIM-format MCQsVignettes with an explanation for every wrong answer.
- Key factsThe numbers and thresholds worth memorizing, up front.
- AI tutorMedBrain answers the question you're stuck on.
What this article covers
- Overview
Scope of this article: the acute crises and chronic complications of established sickle cell disease; baseline pathophysiology, hemoglobin electrophoresis diagnosis, and hydroxyurea disease…
- Epidemiology
Painful crisis burden: a subset of patients with recurrent painful events accounts for most hospitalizations; events per year is inversely related to life expectancy.
- Risk factors
Precipitants of vaso-occlusive crisis: cold exposure, dehydration, infection, hypoxia, acidosis, stress, high altitude, obstructive sleep apnea, pregnancy, and menstruation.
- Pathophysiology
Sickling under hypoxia: deoxygenated hemoglobin S polymerizes, deforming erythrocytes into a rigid sickle shape that adheres to endothelium and occludes the microcirculation.
- Clinical features
Vaso-occlusive pain crisis (most common): sudden severe pain in the extremities, chest, or back in adults, or dactylitis in young children; a clinical diagnosis by history alone, with no test that confirms or excludes pain.
- Differential diagnosis
Osteomyelitis versus bone infarction: both cause severe localized bone pain and fever; blood culture and bone biopsy are required because osteomyelitis (most often Salmonella) needs antibiotics that infarction does not.
- Diagnosis
Each crisis is confirmed by its own clinical pattern, not one unifying test: pain crisis is diagnosed clinically by history alone; ACS requires a new infiltrate on chest imaging plus a respiratory…
- Management
Vaso-occlusive pain crisis: treat pain immediately, do not wait for a workup to complete.
- Complications
Death from acute chest syndrome: the leading cause of mortality, from progression to respiratory and multiorgan failure if transfusion is delayed; multiorgan failure itself is an indication for exchange transfusion.
- Prognosis
Acute chest syndrome severity predicts outcome: prompt transfusion improves survival; delay allows progression to respiratory failure and death.
- Prevention
Penicillin prophylaxis: penicillin V 250-500 mg PO twice daily, continued through childhood and often long-term given lifelong functional asplenia.
Read the whole article
Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.
Related articles
- Sickle cell disease
Sickle cell disease is an autosomal recessive hemoglobinopathy caused by a beta-globin point mutation that produces hemoglobin S, which polymerizes under deoxygenation to sickle erythrocytes and drive chronic hemolysis and vaso-occlusion. Diagnosis is confirmed by hemoglobin electrophoresis or HPLC showing predominant HbS, and lifelong management centers on hydroxyurea, folic acid, penicillin prophylaxis and vaccination for functional asplenia, transcranial Doppler stroke screening, and, in severe disease, transfusion, hematopoietic stem cell transplant, or gene therapy.
- Neutropenic fever
Neutropenic fever is an oncologic emergency defined as a single oral temperature of 38.3 C or higher, or 38.0 C sustained for 1 hour, with an ANC of 500/microL or lower, most often during the chemotherapy nadir. Management is empiric antipseudomonal beta-lactam therapy within 60 minutes, with vancomycin, antifungal therapy, and growth factors added only for specific indications.
- Transfusion reactions
Transfusion reactions are a spectrum of immunologic and non-immunologic complications of blood product administration, ranging from a benign febrile reaction to fatal acute hemolysis, anaphylaxis, TRALI, or septic shock. The first step for any reaction is always to stop the transfusion; the type is then distinguished by timing, hemolysis markers, and hemodynamic and respiratory pattern, and each type has a specific treatment and prevention strategy.