MARCH 17, 2011 Morning Report

Sickle Cell Disease Chronic hemolytic anemia Multiple hemoglobin variants  SS  SC  S-beta thal One of the most common genetic diseases worldwide Geographic distribution corresponds to distribution of malaria  Carrier state is protective

Sickle Cell Disease Pathogenesis  Substitution of valine for glutamic acid  Chromosome 11  Polymerization of deoxygenated Hb  Classic crescent shape  Less deformable cells in the microcirculation Leads to complications

Sickle Cell Disease Diagnosis  NBS  Decreased deaths from pneumococcal infection  Isoelectric focusing  Hb electrophoresis  HPLC  DNA analysis If diagnosed, refer by 3 months to hematology  If not available, see chart

Infection Spleen  Functional asplenia  30% at 1y  90% at 6y  Risk for encapsulated organisms Strep pneumo  Prevention PCN Immunization  Treatment Parenteral antibiotics for all children with fever Ceftriaxone Outpatient or inpatient Resistance and incomplete protection

Infection Osteomyelitis  Salmonella  Staph aureus  Presentation overlaps with VOC  Cannot differentiate on imaging  Diagnosis  Clinical assessment Fever Leukocytosis ESR Positive cultures

Infection Parvovirus B19  Most common cause of transient red cell aplasia  Predilection for young erythroblasts  Plentiful in children with hemolytic anemias  Presentation  Fever  URI  Fatigue  Pallor  Absence of scleral icterus  Decrease from baseline Hb with reticulocytopenia 7-10d  Treatment  Transfusion

Acute Splenic Sequestration Diagnosis  Sudden enlargement of spleen  >2g/dL decrease in Hb from baseline  Reticulocytosis  May also have thrombocytopenia Very rapid <3y of age in HbSS  All other ages of HbS variants Treatment  Volume expanders  Blood transfusions Prevention  Parental education  Clinical signs  Palpating the spleen  Splenectomy  ≥2 events

Acute Chest Syndrome 2 nd leading cause of hospital admissions 50% of SCD patients Age  More common in children  More severe in adults Definition  Radiologic appearance of a new pulmonary infiltrate  Fever  Hypoxia may be present

Acute Chest Syndrome Causes  Infection  Bacteria, viruses, mycoplasma and chlamydia  Fat embolism  VOC  May be due to hypoventilation associated with opioids Treatment  Broad-spectrum antibiotics  Cephalosporin  Macrolide  Oxygen  Hydration  Incentive spirometry  Early transfusion  Exchange if severe

Cerebrovascular Disease Stroke  11% of SS patients <20y  22% silent infarcts  Peak incidence  2-10  Path  Large-arteries Internal carotid Anterior and middle cerebral  Ischemic or thrombotic in 75% (predominately children)

Cerebrovascular Disease Prevention  TCD  Detecting children at risk  Flow velocity >200cm/sec  Screening recommended in all children between 2-16y  Chronic transfusion therapy  HbS <30%  Prevents second stroke in 80%  Reduces stroke risk 10 fold for patients with at risk TCDs

VOC Pain Crises Most distressing symptom Spectrum is wide  34% ≤ 1/year  5% multiple events Frequent admissions <6y is a known RF for death Triggers  Infection  Temperature extremes  Dehydration  Emotional stress

VOC Pain Crises Treatment  Multidisciplinary  Aggressive pain management  Opioids  NSAIDs  Hydration  PT  Ancillary therapy Avg hospital stay 4d  If >10d, must wean opioids

Prognosis Life expectancy  SS  45y  Was 14.3y just 30 years ago  SC  65y