MARCH 17 , 2011

Morning Report

Sickle Cell Disease

Chronic hemolytic anemiaMultiple 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

2nd leading cause of hospital admissions

50% of SCD patientsAge

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 symptomSpectrum 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