Red blood morphology in select enzymopathies.Left panel: in a patient with CNSHA due to PK deficiency, the blood smear is not diagnostic; however, the presence of “prickle red cells” should raise suspicion. From Mahendra et al.⁴⁹ Middle panel: “bite cells,” hemighosts and microspherocytes, characteristic of oxidative hemolysis, are seen in this smear from a child who received a dapsone-chlorproguanyl combination for the treatment of acute P. falciparum malaria. From Pamba et al.⁵⁰ Right panel: red blood cells with fine basophilic stippling in a patient with P5N deficiency. This enzymopathy is the most common inherited cause of basophilic stippling, which is also seen with lead poisoning (lead inhibits many enzymes, including P5N, and it can produce a phenocopy of P5N deficiency). From Rees, Duley, and Marinaki.⁵¹