Check this complete brief detailed overview of Sickle Cell anemia!!

Autosomal recessive disease

G-->V (6th position in the beta-globin)

Homozygous - sickle cell disease

Heterozygous- sickle cell trait

Deoxygenation of heme moiety of HbS  leads to hydrophobic interaction between adjacent HbS

--> aggregates into larger polymer

Sickel RBC -> less deformable and obstruct microcirculation resulting in tissue hypoxia--> further sickling

These RBCs have short life span of 10-20days

Clinical features:

1.Pain

            Vaso-occlusive crisis

           Acute chest syndrome(shortness of breath & dyspnea)

           arthritis and osteomyelitis

2.unilateral weakness, aphasia, paresthesias, visual symptoms--> Stroke or infarct

 3. Sudden increase in pallor, pain, fullness of left side--> splenic sequestration crisis

 4. In young children--> icterus (due to elevated unconjugated bilirubin), pallor and mild splenomegaly

 5. tachypnea--> pneumonia,CCF(Aplastic crisis), acute chest syndrome( hypoxia common)

 6. febrile illness( Pneumococcal, salmonella & other bacterial infections)

 7.Hypotension and tachycardia ( signs of septic shock or sequestration crisis)

8. Growth retardation and gallstones common

Types of crisis

1. Vaso-occlusive crisis:

• CVA
• Retinal hemorrhages
• Dactylitis
• Acute chest syndrome
• Hand and foot syndrome
• Acute abdomen
• Auto-infarction of spleen
• Kidney--> papillary necrosis--> isosthenuria
• Priapism
• AVN of femoral head

2. Acute chest syndrome

3. Sequestration crisis

4. Aplastic crisis

      - parvovirus B19

Infections:

 Susceptible to encapsulated organisms(Haemophilus influenza, streptococcus pneumonia)

More prone for Salmonella, Mycoplasma pneumonia, staphylococcus aureus and Escherichia coli

Lab studies:

Anemia

Thrombocytosis

Leukocytosis

Peripheral smear--> sickle RBC & target cells

Howell-Jolly bodies--> Asplenic

Indirect bilirubin elevated --> chronic  hemolysis

Hemoglobin electrophoresis--> differentiates between homozygous and heterozygous

Investigations:

Pain crisis--> Xray chest and bones

Blood culture

Respiratory  crisis--> Monitor oxygen saturation and ABG

Splenic sequestration or aplastic crisis--> major drop in Hb( Reticulocyte count and splenic examination done to differentiate between them)

ECG

Management:

Pain crisis:

1. Hydration

                  corrected orally if the patient tolerates oral supplements

                   intravenous fluid  in severe dehydration

                   Blood transfusion useful in patient with aplastic crisis and acute sequestration crisis

2. Analgesia --> narcotic analgesic is most frequently used

3. Oxygen supplementation --> if hypoxia present

4. Intubation and mechanical ventilation --> CVA or Acute chest syndrome

5.Exchange transfusion(in acute sequestration crisis & priapism patient)--> replacing patient's RBC with normal donor RBC --> reducing HbSS to <30%

Preventive care:

Penicillin or amoxicillin( up to 5 yrs)

Immunizations( pneumococcal, meningococcal, Hib)

Lifelong folate supplementation

Hydroxyurea

Regular monitoring --> to screen gallstones

Genetic counseling and testing