In detail

Sickle cell anemia

Sickle cell anemia


It is characterized by the presence of hemoglobin S and occurs in homozygotes for the gene for sciatica. The cyclic characteristic is transmitted dominant. Feature carriers have both hemoglobin A and hemoglobin S, while patients have only hemoglobin S. The cyclization process is often triggered by decreased oxygen and ph pressure. The slow movement of the drepanocyte (erythrocyte in the sickle) through capillary causes frequent thrombus formation, and thrombosis can provide explanation for three clinical manifestations:

  • Abdominal pain
  • Pain in the limbs
  • Autosplenectomy (progressive decrease of spleen volume)
    Its main focus is African (West and Equatorial Africa). In some regions, the frequency of the cyclic trait (homozygous and heterozygous subjects for the pathological gene) reaches 25%. This hemoglobinopathy is also found in Greece, the Middle East, Madagascar and India.
    Clinical signs and symptoms:
    The patient presents with asthenia (fatigue) and moderate anemia, usually accompanied by a discrete conjunctival jaundice. Painful bone, joint or abdominal crises often occur until redness and stiffness. The seizure is usually concomitant with: severe acute hemolysis, anemia, jaundice, fever and marked weakness. The growth is delayed, the children are asthenic, and in the older ones the enlargement of the bones of the face and the cranial cap is observed, the appearance becoming turichal.
    hematologic, the normal hemoglobin level is 7-9% but it drops to 2-3g% in the crisis. Nuclear (with nucleus) erythrocytes are present in large numbers (can equate leukocytes numerically). Indirect serum bilirubin is slightly increased. electrophoretic, the presence of hemoglobin S and hemoglobin F is detected (the latter being between 5-20%)
    radiological, we find:
  • Thinning of the cortex of the bones with enlargement of the medullary spaces
  • accentuated trabecular drawing.
    diagnosis positive is based on permanent anemia with:
  • jaundice
  • increased reticulocytosis
  • hemolytic seizures
  • hemoglobin S and hemoglobin F
  • positive cyclization test
  • early splenomegaly with progressive diminution in childhood until disappearance
  • pain in the limbs
  • abdominal pain
    the diagnosis differential it is done first, with the other hemoglobinopathies, then with the hematuria of another cause (there are cases of hemoglobia with hematuria), then with:
  • acute appendicitis (in the abdominal painful seizures of siclemia)
  • the cyclic characteristic associated with anemia due to iron deficiency (it is characterized by a low number of reticulocytes, hypochromia and only higher erythrocytes)
    complications possible are:
  • vascular thrombosis (cerebral thrombosis, pulmonary infarction - in young children)
  • leg ulcers
  • aseptic necrosis of the head of the femur (in older children)
  • increased incidence of osteomyelitis
  • cardiomegaly until heart failure in adolescents (due to severe, prolonged anemia and cardiac ischemia)
  • aplastic seizures with severe and prolonged anemia
    Treatment it is necessary in the seizure (either hemolytic or aplastic) and consists of blood transfusions (there is no effective method to prevent seizures or prevent chronic haemolysis). Total blood (preferably) or erythrocyte mass is used. In the crisis of use in addition:
  • oxygen
  • rehydration
  • acidosis correction
    In mild cases, rest and sedatives may be sufficient. Corticotherapy can positively influence painful symptoms. Testosterone, recommended for stimulation of hematogenous production, increased the incidence of thrombosis. There are no objective criteria for assessing the impact of urea treatment on the cyclization phenomenon. Splenectomy is required only if the hypertrophy is large and persistent, requiring repeated transfusions, because there is a spontaneous tendency to reduce the size of the spleen.
    prognosis
    Death rarely occurs in childhood due to severe infections, strokes or heart failure. It usually occurs in adulthood through progressive kidney failure with uremia or heart failure.
    Syclic trait (heterozygous form of sciatica) is common in the black race. It is generally asymptomatic, absent: anemia, morphological changes of erythrocyte and reticulocytosis.
    Complications: progressive alteration of the urine concentration capacity with:
  • sometimes hematuria in 3-4% of cases
  • pulmonary or splenic infarcts favored by altitude (low oxygen pressure)
    The prognosis is good