Hemoglobin Variant (Hemoglobin Aalborg) Mimicking Interstitial Pulmonary Disease

Abstract

Hemoglobin Aalborg is a moderately unstable hemoglobin variant with no affiliation to serious hematological abnormality or major clinical symptoms under normal circumstances. Our index person was a healthy woman of 58, not previously diagnosed with hemoglobinopathy Aalborg, who developed acute respiratory failure after a routine cholecystectomy. Initially she was suspected of idiopathic interstitial lung disease, yet a series of tests uncovered various abnormal physiological parameters and set the diagnosis of hemoglobinopathy Aalborg. This led us to examine a group of the index person's relatives known with hemoglobinopathy Aalborg in order to study whether the same physiological abnormalities would be reencountered. They were all subjected to spirometry and body plethysmography, six-minute walking test, pulse oximetry, and arterial blood gas samples before and after the walking test. The entire study population presented the same physiological anomalies: reduction in diffusion capacity, and abnormalities in PaO2 and p50 values; the latter could not be presented by the arterial blood gas analyzer; furthermore there was concordance between pulse oximetry and arterial blood gas samples regarding saturation. These data suggest that, based upon the above mentioned anomalies in physiological parameters, the diagnosis of hemoglobinopathy Aalborg should be considered.

Hemoglobin Aalborg Causing Low Oxygen Saturation in a Child

“…Despite the low peripheral oxygen saturation, oxygen unloading to the tissue is considered normal with no negative effects such as tissue hypoxia [6]. One study looking at six adult family members with hemoglobin Aalborg reported a concordant low peripheral and arterial oxygen saturation as well as low diffusion capacity for carbon monoxide [3]. Our patient had a high arterial and a low peripheral oxygen saturation on blood gas analysis, as well as a normal DLCO.…”

“…Hemoglobin Aalborg has a reduced oxygen affinity due to the altered state of the hemoglobin molecule in the tense and relaxed state [3,6]. This change shifts the oxygen dissociation curve to the right with an increase in the P50.…”

“…Hemoglobin Aalborg is one such variant, and was originally reported in some adult patients in Denmark. It is rare, relatively unstable hemoglobin with low oxygen affinity and no significant clinical or hematological complications under normal physiological conditions have been described [3]. Patients who have inherited low affinity oxygen hemoglobin such as hemoglobin Aalborg could have low peripheral oxygen saturations despite normal oxygen delivery to tissues.…”

A Case of Hb Aalborg (HBB: c.223G>C) with Chronic Obstructive Pulmonary Disease: A First Familial Presentation in Japan

“…Hb Aalborg is moderately unstable and is associated with mild anemia [4]. In addition, Hb Aalborg has a reduced oxygen affinity due to the altered state of the Hb molecule in the tense and relaxed state [5,6]. This change shifts the oxygen dissociation curve to the right with an increase in the p50.…”

“…A few years ago, Panou et al [5] reported a Hb Aalborg patient who developed acute respiratory distress syndrome (ARDS), such as interstitial lung disease (ILD)-like clinical symptoms after cholecystectomy surgery. They reported that six out of seven cases caused 59.0-76.0% of %DLCO decrease and found no pulmonary disease.…”