Hemoglobin Cheverly: an Unstable Hemoglobin Associated with Chronic Mild Anemia

Abstract

SummaryThe evaluation of a family with chronic mild anemia led to the identification of a new unstable hemoglobin (Hemoglobin Cheverly). Modest anemia and reticulocytosis, normal to slightly increased mean corpuscular volume (MCV), and normal mean corpuscular hemoglobin concentration (MCHC) were present in the affected family members. Electrophoresis of blood samples on cellulose acetate and on citrate agar revealed normal patterns. Globin chain analysis and isoelectric focusing data were also normal. After incubation for 3 h at 41°C, Heinz bodies were detected in 95-100% of erythrocytes from affected individuals. Positive heat and isopropanol tests confirmed the initial observation of the Heinz body preparation and indicated that an unstable hemoglobin was present. Structural analysis showed an amino acid substitution of Phe-Ser at position 45 (CD4) in the P chain.

A Family of Three with Haemoglobin Cheverly: Low Oxygen Saturation in Stable Patients

“…Another case in 1983 involved a family of three from Baltimore with chronic mild anaemia. 5,6 An observational study done in Germany showed that only 9 out of 34,228 persons had Hb Cheverly. 7 Hb Cheverly is caused by point mutation with the replacement of thymidine by cytosine and subsequently the substitution of the amino acid phenylalanine (Phe) by serine (Ser) at the CD4 region in the haem pocket, at codon 45 of the beta globin chain.6 This weakens the Hb interaction, rendering the instability of the mutated beta globin chain, leading to a mild haemolytic anaemia.…”

“…At our hospital, her pulse oximetry consistently showed readings below 85%. However, an arterial blood gas analysis Clinical A family of three with haemoglobin Cheverly: low oxygen saturation in stable patients Lai Chee Chow 1 , Soo Huan Puah 2 , Xun Ting Tiong 3 , Nisha Sabrina Aloysious 4 , Tze Shin Leong 5 , Lee Ping Chew 6 showed good oxygenation with partial pressure of oxygen in arterial blood (PaO 2 ) of 554.9 mmHg under HFMO2 15 L/ min and PaO 2 of 99.3 mmHg under room air. The arterial oxygen saturation (SaO 2 ), methaemoglobin (metHb) and carboxyhaemoglobin (COHb) were normal.…”

Oxygen Saturation of 75%, but No Symptoms!

“…Most of the qualitative hemoglobinopathies have frequencies below 1% and can be associated with various or even no clinical manifestations [8]. In 1982 and 1983, an elderly Italian male with cyanotic heart disease [9] and an anemic female in Baltimore [10] were the first patients described with the Cheverly variant hemoglobin. In a German observational study, over a period of four decades, only 9 patients within hemoglobin Cheverly have been found [11].…”