Thirty-four blood samples of neonates in Dubai, UAE, with an MCV below 90 fL were checked by high performance liquid chromatography (HPLC) for hemoglobin variants to confirm a previous study carried out in Western Province of Saudi Arabia which showed a very high predictive index of such MCV for alpha (α-) thalassemia minor (ATM). MCH below 30 pg was an additional factor which supported such a prediction. The Dubai study confirmed the original finding with 100% of such neonates showing Hb Barts band. A control group of 26 neonates with an MCV between 90 and 95 fl showed Hb Barts in only 11 cases (42.3%). Of these, 6 (23.1%) were preterm babies, expected to have higher MCV. Five cases (19.2%) had an MCH below 30 pg, though MCV was 90 or higher. Three of the preterm babies also had MCH below 30. The study confirmed the Saudi results in neonates. It seems very highly probable that a term neonate with MCV below 90 and MCH below 30 has ATM.

Two families with 'factor X(FX)-Riyadh' have been identified (one of them related to the originally reported family). Affected members of both families exhibit prolongation in prothrombin time (PT) with normal partial thromboplastin time (PTT) and low assay levels of FX, when measured by PT-based assay. They do not have clinical bleeding diathesis, regardless of the PT prolongation. FX genes of the affected family members were analyzed by sequence analysis. A novel missense mutation in exon 4 of the FX gene, which causes the Glu51Lys substitution in the first epidermal growth factor-like domain of FX was found. The Glu51Lys mutation represents a type II mutation with low FX coagulant activity in the extrinsic pathway and normal FX antigen levels. This mutation may result in disruption of the predicted H-bonding between residue Glu51 of FX and the Asn199 residue of the tissue factor (TF) in the FX/TF/factor VIIa ternary complex, producing the phenotype 'FX deficiency Riyadh', with prolonged PT and normal PTT.

One hundred consecutive patients with hemoglobin concentration less than 3.5 g/dL (hematocrit reading, less than 10%) were admitted to the University of Baghdad Teaching Hospital, Iraq, during a 30-month period. Twenty-eight patients had aplastic anemia, 27 had leukemia or other hemopoietic malignancies, 16 had chronic renal failure, eight had iron-deficiency anemia, eight had hemolytic anemia, seven had thalassemia major, and six had other conditions. Twenty-three patients died within seven days of admission, mostly due to the underlying disease or complications thereof. Heart failure developed in ten patients, and five had retinal exudates and hemorrhages attributed to severe anemia. Arrhythmias and ECG abnormalities were noted in 20 of 68 patients. Blood transfusion was instituted in all but three patients, whose anemia was corrected with specific therapy without blood transfusion. The tolerance of the 100 patients to such severe anemia was remarkable.

To assess some simple blood parameters at birth that can be used as a basis to suspect α-thalassemia minor (ATM), a prospective study involving 202 consecutive neonates with MCV of less than 95 fl or less were checked for Hb Barts by HPLC. The group was divided into two, one with an MCV of 90-95 (89 cases) and the other with an MCV below 90 (113 cases). For control, 104 consecutive neonates with an MCV Ͼ 95 fl were similarly checked. It has been confi rmed that an MCV that is below 90 fl , especially with and MCH of Ͻ30 pg is a strong indicator of the presence of ATM (109/113). On the other hand, MCV of 90 or more, especially with an MCH of 30 or more is a strong negative indicator for ATM (70/89). Firm diagnosis of ATM at birth can thus be secured in majority of neonates.

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