Prevalence of Hepatitis B and C among Thalassemia and Sickle Cell Disease Patients in Al Ahsa region, 1428 H.

Sickle cell disease and Beta Thalassemia major are common diseases in Saudi Arabia, especially in Al Ahsa region, and are associated with high morbidity and mortality. Blood transfusion is the mainstay of management of these patients, which places them at a definite risk of acquiring blood-borne diseases, such as hepatitis B and C, which could add to their suffering. The objective of this study was to assess the prevalence of Hepatitis B and C among Sickle Cell Disease (SCD) and Thalassemic patients in Al Ahsa region. The study was conducted as a cross-sectional health facility based survey, based on patient’s records and interview. The study involved 75 thalassemia patients registered at the Thalassemia center, and 251 sickle cell disease patients registered at King Fahad Hospital, Prince Bin Jalawy Hospital and Maternity and Children Hospital in Hofuf .

The age of SCD patients ranged from 7 to 55 years (mean 22.1 ± Standard Deviation (SD) 10.2 years). Males constituted 47.4% and females 52.6%. All were Saudis except for one Palestinian. Of the total, 58.6% had been diagnosed below 5 years of age, 31.1% were diagnosed at age between 6-10 years, and 10.3% were diagnosed at 11 years and above (mean 6.4 years, SD ± 4.8). Based on hemoglobin electrophoresis at time of diagnosis, only 0.8% had HbS above 90%, 15.1% had HbS ranging from 81-90%, 38.2% had HbS ranging from 71-80%, 31.1% had HbS ranging from 61-70% and 14.7% had HbS ranging from 50-60%. Of the total, 29.9% also had G6PD deficiency.

The majority of SCD patients (90.4%) had received blood transfusions through their lives. Regarding the number of blood units transfused over the whole life, 59.4% had received 1-5 units, 18.3% had received 6-10 units, and 12.7% had received 11 or more units (Mean blood units transfused 6.4, SD ± 4.8). Hemolysis was the most common indication for blood transfusion (51.0%), followed by post-operative blood transfusion (13.7%), and infection (13.7%). Among SCD patients, 70.1% had some dental procedure and 45.0% had some surgical procedure performed in their life. Surgical procedures performed included cholecystectomy (58.7%), splenectomy (13.2%) and Hip replacement (4.9%).

Of the total SCD patients, 18.3% had positive hepatitis C virus (anti-HCV) antibodies, 1.2% were HBsAg positive, and 0.4% had both anti-HCV and HBsAg positive.

As shown in table 1, higher age (P<0.001), higher number of blood units transfused (P=0.01), higher number of dental procedures (P=0.03) and having a surgical procedure (P=0.04) were found to be significantly associated with being Hepatitis C positive in SCD patients; while no association was observed with gender.

Regarding the 75 Beta thalassemia patients, 46.7% were male. Their ages ranged from 2 to 30 years (mean 12.8 years, SD ± 6.1). Among the total, 30.7% were diagnosed under 1 year of age, 53.3% at age 2 to 3 years, and the rest were diagnosed between 4 to 5 years of age. All thalassemic patients were vaccinated against hepatitis B. All received regular blood transfusions every 3-4 weeks; 21.3% had received up to 50 units of blood throughout their lives, 26.7% had received between 51-100 units, 32.0% between 101-150 units, and 20.0% over 151 units (mean 104.9 units, SD ± 66.2). Of the total, 42.6% had some dental procedure and 18.7% had some surgical operation performed during their life. Among those who had surgical operations, 78.9% had splenectomy and 21.4% had cholecystectomy. Of the total, 13.3% had positive hepatitis C virus antibodies (anti-HCV) and none had positive HBsAg.

There was a statically significant association between Hepatitis C and the number of blood units received, the highest proportion of hepatitis C (46.7%) was among patients who had received over 150 blood units (P<0.001). Hepatitis C was found among 28.1% of Beta thalassemia patients who had received dental treatment compared to 2.3% among those who had never received any dental treatments (P=0.001). Among those who had some surgical procedure, 28.6% had hepatitis C, compared to 9.8% among those who had not (P=0.08).

In spite of the fact that the prevalence of Hepatitis B has fallen after introduction of the vaccine, to less than 2% in Western Europe and North America, it remains high in developing countries, up to 8%.⁵ In the absence of vaccine against hepatitis C, infection remains a major public health problem worldwide. The World Health Organization estimates that about 170 million people, or about 3% of the world population, are infected with hepatitis C.⁶

In this study the prevalence of Hepatitis C was 18.3% among SCD and 13.3% among Beta thalassemia patients, while Hepatitis B was found among only 1.2% of SCD patients and none of the Beta thalassemia patients. This major difference between both disease groups can be attributed to the availability of vaccination against Hepatitis B, that does not exist for Hepatitis C. All Beta thalassemic patients had received three complete doses of hepatitis B vaccine, while 54.4% of SCD had not. It should be mentioned that there is a protocol of regular screening of Beta thalassemic patients every 6 months for Hepatitis B markers and immunity, whereby if the immunity is found to be low, the patient would be

given another series of vaccine, which is not the case among SCD patients. As no vaccination against Hepatitis C is likely to be available in the near future, extra care should be taken in the implemention of general preventive measures against blood-borne infection to reduce the prevalence of hepatitis C among these patients.

SCD and Beta thalassemia patients are particularly at risk to undergo certain operations, such as splenectomy and cholecystectomy, which can place them at higher risk of acquiring Hepatitis B and C. This study confirmed the association between Hepatitis C infection and surgical procedures particularly among SCD patients.

References:

1-Al-Suliman A. Prevalence of ß-thalassemia trait in premarital screening in Al-Hassa, Saudi Arabia. Ann Saudi Med 2006;26(1):14-16.

2- Schnog JB, Duits AJ, Muskiet FA, Cate HT, Rojer RA, Brandjes DP. Sickle cell disease: a general overview. The Netherlands J Med 2004;62(10):364-73.

3- Alseed HH, Al-Salem AH. Principle of blood transfusion in sickle cell anemia. Saudi Med J 2002;23(12):1443-1448.

4-Al-Awamy BH. Thalassemia syndromes in Saudi Arabia, meta-analysis of local studies. Saudi Med J 2000;21(1):8-17.

5- World Health Organization Programmes and projects, media centre, Fact sheet No. 204. Hepatitis B. Revised Oct 2000; cited Oct 26, 2007. Available from: http://www.who.int/mediacentre/factsheets/fs204/en/

6- World Health Organization Programmes and projects, media centre, Fact sheet No. 164. Hepatitis C. Revised Oct 2000; cited Oct 26, 2007. Available from: http://www.who.int/mediacentre/factsheets/fs164/en/

Table 1: Demographic characteristics, and risk factors for Hepatitis B and C among SCD and Thalassemia patients, Al Ahsa, 1428 H.