A Multicenter Study On Hereditary Spherocytosis In Lebanon
Authors: Inati Adlette , Noun Peter , Kabbara Nabil , Salloum Cynthia , Kmeid Michel , Sadek Maroun , Kahale Mario , Abbas Hussein A 
Published: October 2019

Introduction
Hereditary spherocytosis (HS), the most common cause of inherited chronic hemolysis in Northern Europe and North America, is characterized by a wide variety of clinical features, ranging from an asymptomatic condition to a fulminant hemolytic anemia. Guidelines regarding the management and diagnosis of HS have been updated in 2012. Few reports exist on HS prevalence and related molecular abnormalities in Mediterranean populations. The prevalence and features of HS in Lebanon have not yet been reported. The aim of this study is to determine demographic, clinical, hematological and therapeutic features as well as outcome of a group of Lebanese patients with HS.

Methods
This is a retrospective hospital-based surveillance study conducted at 4 centers in Northern Lebanon and Central Beirut. Data was collected from archived files on 31 patients between May 2012 and May 2013 and included patients’ demographics, clinical presentation, diagnostic laboratory tests, treatment modalities and outcome. Analysis was conducted using SPSS 19, and t-test was used to compare two groups. We also conducted an Analysis of Variances where we included demographic variables that were different between the two groups as covariates (ANCOVA) in order to look for group effect. Statistical significance was set at p<0.05.

Results
Thirty one patients, median age at diagnosis 60 months, age range 11 -.180 months were included in this study. 58.1% and 41.9% were females and males. 54.8% (17/31) had a family history for HS and 32.3% (10/31) had one parent with HS. The predominant clinical manifestations at diagnosis were pallor in 27/31 (87.1%), splenomegaly in 23/31 (74.2%) and anemia in 20/31 (64.5%) patients respectively. The mean size of the spleen at diagnosis was 5.51±2.91 cms below the costal margin. 9.7 % of patients had symptomatic gallstones.
The mean hemoglobin, MCV, MCHC and reticulocyte count at time of diagnosis were 8.7 ± 2.1 g/dL, 73.0 ± 9.9 fL/red cell, 34.13±2 g/dl and 6.58±4.2% respectively. 13/17 (68.4%) had spherocytes on baseline blood smear. Osmotic fragility test performed in 27/31 (87.1%) was compatible with diagnosis of HS in 88.24 % patients. HPLC performed in 17/31 (54.8%) showed a mean HbF of 3.82 % and sickle cell trait in 4/17(2,35%) patients. 5/19 (26.3%) had concomitant G6PD deficiency.
Folic acid supplementation was provided to patients with moderate to severe disease. 23/31 patients (74.2%) required intermittent or regular blood transfusions and 10/31 patients (32.3%) underwent splenectomy as part of their treatment. All splenectomies were done after 5 years of age except in one patient who had recurrent severe hemolysis necessitating splenectomy at 3 years. There were no correlations between the need for splenectomy with age at diagnosis (p-value 0.97), MCHC level (p-value 0.43) and blood type (p-value 0.17). There was a positive correlation between the need for splenectomy and the need for blood transfusion (r=0.671; p=0.006) and between G6PD status and the need for transfusion (r=0.778; p=0.002). 30/31(96%) patients are alive and doing well while 1 patient died from acute splenic sequestration. Of the 30 surviving patients, 3 (10%) had had a complicated disease course characterized by very severe and early hemolysis in 2 patients and significant iron overload in a third patient.

Conclusions
This is the first study from Lebanon describing the demographic, clinical, hematological and therapeutic features as well as outcome of patients with HS. Data generated from this study suggest underreporting of the disease and over utilization of the osmotic fragility test underscoring the need to initiate more awareness amongst Lebanese health providers about this disease and its new diagnostic guidelines. Clinical features, therapeutic modalities and excellent patients’ outcome in this Lebanese group appear to be similar to modern published reports. Major limitations of this study include its retrospective design and the small sample size. Prospective studies with long term follow up and enrolling a larger sample size are needed to better assess the utility of newer diagnostic tests and the long term complications associated with splenectomy.

Disclosures:
No relevant conflicts of interest to declare.