Sickle Cell Disease
SSD
HbS
AR inheritance
Africa, West Asia, South Asia
Characterised by
Acute chest syndrome
Splenic sequestration crisis
Aplastic crisis
Infections
HbS
AR inheritance
Africa, West Asia, South Asia
Characterised by
- Haemolytic anaemia
- vasoocculsion and tissue infarct (inc autosplenectomy)
- (Avoid G-CSF, triggers vaso-occlusion
Acute chest syndrome
- HbS deoxigenates in lung (trigger infection or fat embolism from crappy marrow) > Sickles > Vasoocclusion > ischemia
- Dx: New pulmonary infiltrate (not atelectasis) AND
- Chest pain OR Temp >38.5C OR Resp signs on Ex OR hypoxemia
Splenic sequestration crisis
- vaso-occlusion and pooling of RBCs in spleen, hypovolemia > shock > death (10-15%)
- Ex large tender spleen
- Ix acute drop in Hb, low Plt, high retics
- Rx Isotonic saline, care with PRBC as can have sudden release of sequested and then iatrogenic polycythemia and hyperviscosity syndrome ie transfuse 50% of normal
- Prognosis: high recurrence in within 1y
- Rx self palpation of spleen, consider splenectomy`
Aplastic crisis
- SSD involved rapid turnover, lysis is the problem, if production is interrupted > aplastic crisis
- parvovirus (no. 1), Strep. pneumonia, Salmonella, EBV
- Rx is PRBC
- last 2-14d
Infections
- Encapsulated: Strep pneumonia, HiB (related to autosplenectomy
- Salmonella, E.coli, Staph (?related to micro infarcts allowing penetration)