3801 3802 Children may have an acute splenic sequestration syndrome or can develop splenic auto-infarction. This commonly occurs between 10 and 27 months of age. Acute splenic sequestration syndrome involves acute splenic enlargement from increased intrasplenic sickling and obstruction. Rapid sequestration results in a rapidly falling RBC count and circulatory collapse.28 A Hb drop by greater than 4 g/dL is associated with 35% mortality in the pediatric population.23 Emergency manage- ment is aimed at restoring circulating blood volume with transfusion. Splenectomy is curative, although asplenia results in an increased risk of infection with encapsulated organisms such as Streptococcus pneu- moniae or Haemophilus influenzae. Autosplenectomy occurs as a result of occlusion of the splenic artery, leading to infarction and functional asplenia.23,25 3803 3804 Bacterial infections are common due to functional asplenia, and may result in life threatening pneumonia, sepsis, or meningitis, espe cially in infancy or childhood. Pneumococcal vaccination has dramat ically reduced the incidence of invasive pneumococcal disease in sickle cell patients and is a mainstay of preventative therapy, in addition to H. influenza type b and meningococcal vaccination series. Prophy lactic daily antibiotics, with either amoxicillin or penicillin, are usu ally required for all children 2 months to 5 years old with functional asplenia.23,25 A WBC count, blood cultures, urine cultures, and a chest radiograph should be considered in the evaluation of a febrile patient 3805 3806 *TABLE 109.7 Organ Damage Seen in Sickle 3807 Cell Disease* 3808 3809 3810

Organ or System	Injury
Skin	Stasis ulcer
Central nervous system	Cerebrovascular accident
Eye	Retinal hemorrhage, retinopathy
Cardiac	Congestive heart failure
Pulmonary	Intrapulmonary shunting, pulmonary hypertension, embolism, infarct, infection
Vascular	Occlusive phenomenon at any site
Liver	Hepatic infarct, hepatitis resulting from transfusion, hepatic sequestration, intrahepatic cholestasis
Gallbladder	Increased incidence of bilirubin gallstones caused by hemolysis
Spleen	Acute sequestration
Urinary	Hyposthenuria, hematuria, glomerulosclerosis, end-stage renal disease
Genital	Decreased fertility, impotence, priapism
Skeletal	Bone infarcts, osteomyelitis, aseptic necrosis
Placenta	Insufficiency with fetal wastage
Leukocytes	Relative immunodeficiency
Erythrocytes	Chronic hemolysis

3811 3812 with sickle cell disease. Early institution of appropriate antibiotics, such as ceftriaxone 1 to 2 g IV or IM with consideration for vancomycin 15 mg/kg IV, is necessary in patients with a discernible source of infection or sepsis. An increased incidence of Salmonella osteomyelitis occurs in sickle cell patients and should be considered in the differential. The origin of immunologic deficiency in sickle cell disease is believed to be multifactorial, involving functional asplenia leading to increased infection risk with encapsulated organisms, poorly migrating neutrophils, and decreased opsonin production. 3813 3814 Major, chronic organ damage in patients with sickle cell anemia is common (Table 109.7). Severe, life threatening multi-organ failure [... Output truncated due to length. 3059 tokens/12073 characters removed ...]