Page 197 - Haematologica Atlas of Hematologic Cytology

CHAPTER 21 - Pure red cell aplasia
Chapter 21. PURE RED CELL APLASIA
Pure red cell aplasia (PRCA) is a rare disorder characterized by normochromic-normocytic or normochro- mic-macrocytic anemia, marked reticulocytopenia, and almost complete absence of the erythroid precursors in the bone marrow. In most cases, the granulocytic and megakaryocytic lineages are normal (Means, 2016). This disorder includes congenital and acquired conditions (Table 1).
Table 1. Classification of pure red cell aplasia.
Category
ondi on
Congenital
Diamond-Blackfan anemia
Acquired
Primary
Idiopathic
Autoimmune
Secondary
Thymoma
Hematologic malignancy (especially lymphoid neoplasms)
Solid tumor
Infec on (parvovirus B19, CM , EB , HI , HH -6, , viral hepa s, Leishmaniasis, Gram-posi ve sepsis)
Autoimmune condi ons
Chronic hemoly c anemia (aplas c crisis)
Exposure to drugs (erythropoie n, isoniazid, azithromycin, phenytoin) Other (renal failure, pregnancy)
CM : cytomegalovirus; EB : Epstein-Barr virus; HI : human immunode ciency virus; HH : human herpesvirus; : varicella zoster virus.
Diamond-Blackfan anemia is a chronic disorder which usually presents in early infancy with an autosomal domi- nant inheritance in 50% of cases, some mes associated with physical malforma ons (Ramenghi et al., 1999; Lipton and Ellis, 2009). Acquired PRCA may occur in children or adults and may be acute or chronic. In young children, an acute form of PRCA called “transient erythroblastopenia of childhood” may be observed; it is usually caused by viral infec ons, especially infec on by human herpesvirus 6, lasts a few months, and does not need to be treated. In older children and adults, the most common form of acute PRCA is due to parvovirus infec on (Luo et al., 2013). In immunocompromised pa ents, parvovirus infec on can cause a chronic form of PRCA.
Diagnosis is based on hematologic ndings (normochromic/normocy c or normochromic/macrocy c anemia with re culocytopenia) and bone marrow morphological aspects (hypoplasia or aplasia of the erythroid lineage, mainly represented by proerythroblasts with <0.5% maturing erythroblasts, and normal matura on of the granu- locy c and megakaryocy c lineages), in the absence of extramedullary hematopoiesis.
As red cell aplasia can some mes be the dominant manifesta on of a myelodysplas c syndrome, a careful se- arch for dysplas c features in the other bone marrow lineages is essen al in order to make a di eren al diagnosis.
References
Lipton JM, Ellis SR. Diamond Blackfan anemia: diagnosis, treatment and molecular pathogenesis. Hematol Oncol Clin North Am. 2009;23(2):261-282.
Luo , Kleiboeker S, Deng X, iu J. Human Parvovirus B19 infec on causes cell cycle arrest of human erythroid pro- genitors at late S phase that favors viral DNA replica on. J irol. 2013;87(23):12766-12775.
Means RT Jr. Pure red cell aplasia. Hematology Am Soc Hematol Educ Program. 2016;2016(1):51-56.
Ramenghi , Garelli E, altolina S, et al. Diamond-Blackfan anemia in the Italian popula on. Br J Haematol. 1999;104:841-848.
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