Stroke among Children with Sickle Cell Anemia in Mulago Hospital, Uganda

Research Article

Austin Pediatr. 2017; 4(2): 1055.

Stroke among Children with Sickle Cell Anemia in Mulago Hospital, Uganda

Munube D¹*, Lwabi P², Ndeezi G¹, Katabira E³, Mukasa MK³, Joloba M4, Lhatoo S5, Sajatovic M6 and Tumwine JK¹

¹Department of Pediatrics and Child Health, School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda

²Uganda Heart Institute, Mulago Hospital, Kampala, Uganda

³Department of Internal Medicine, School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda

4Deparment of Microbiology, School of Biomedical Sciences, College of Health Sciences, Makerere University, Kampala, Uganda

5Department of Neurology, University Hospitals – Case Medical Centre, Cleveland, USA

6Neurological and Behavioral Outcomes Centre, University Hospitals – Case Medical Centre, Cleveland, USA

*Corresponding author: Deogratias Munube, Department of Pediatrics and Child Health, School of Medicine, College of Health Sciences, Makerere University, Kampala, Uganda

Received: April 13, 2017; Accepted: May 15, 2017; Published: May 22, 2017

Abstract

Background: Sickle Cell Anemia (SCA) is a leading cause of child morbidity and mortality affecting 4% of all newborns in Uganda. Stroke is a serious complication of SCA in childhood and 10% of patients with SCA will have had a stroke by the age of 20 years. Hitherto there has been limited information on SCA stroke in Uganda.

Objective: To describe the clinical presentation of children with SCA stroke; and hematological indices and interventions in those with a stroke.

Method: We studied 46 SCA children aged 2–18 years attending the sickle cell services of Mulago Hospital in Uganda from February to June 2011. Numerical data was summarized into mean +/- standard deviation for normally distributed variables and ranges +/- inter-quartile range for skewed data. Categorical data was summarized into percentages.

Results: Forty six SCA children with stroke are described in this case series. The median age at first stroke was 4 years [Inter-quartile range (IQR) 2-6]. Symptoms of children with SCA stroke included behavior changes, headache and seizures. Findings on physical examination included hemiplegia, aphasia, and limb ataxia. Four of the 46 children with SCA stroke had a sickle cell hemoglobin (HbS) <30%. Ninety five percent (44/46) of the children had received a blood transfusion.

Conclusion: Children with stroke in sickle cell anemia presented with a range of neurological symptoms and signs. Further research is needed to determine the risk factors for stroke in our population.

Keywords: Sickle Cell Anemia; Stroke; Children; Uganda

Introduction

Sickle Cell Anemia (SCA) is a common genetic condition due to a hemoglobin disorder in which there is inheritance of mutant hemoglobin genes from both parents [1]. It is the commonest inheritable disease in Africa [2]. In Uganda it is a leading cause of child morbidity and mortality affecting 4% of all newborns [3]. Stroke is a leading cause of mortality in SCA and approximately 10% of patients in North America will have had a stroke by the age of 20 years [4]. Stroke in patients with SCA involves large vessels in the arterial circulation. The internal carotid and the middle cerebral arteries are particularly affected and may present as cerebral infarction or hemorrhage [5].

The risk of stroke is highest during the first decade especially in children aged 2 to 5 years [4]. The risk is lowest before the age of 2 years, probably because of the protection, against sickling, accorded by fetal hemoglobin [4,5]. It has now been established that a child with SCA has a stroke risk that is 300 times more than that of a child without SCA [4,5].

While stroke complicating SCA has been reported from several studies in Nigeria, Cameroun and Kenya [6,7], it has not been reported from Uganda.

In this study, we describe the clinical features of children with SCA who had suffered a stroke attending Mulago Hospital, Uganda’s National Referral Hospital.

Methods

In this case series, we describe the SCA children who suffered a stroke. In this study, Stroke was defined using the World Health Organization definition of stroke: “rapidly developing clinical signs of focal (or global) disturbance of cerebral function, with symptoms lasting 24 hours or longer or leading to death with no apparent cause other than of vascular origin [8]. The study was carried out in the Sickle Cell Clinic and Pediatrics wards of Mulago Hospital, in Kampala, Uganda from February to June 2011. The Sickle Cell Clinic has 12,000 registered patients, with an average monthly attendance of 600 and an average daily attendance of 30-40 patients. The clinic runs daily from Monday to Friday. The study investigators recruited, and performed physical examinations among the study participants. A sample of whole blood was collected from the study participants using aseptic techniques during the study period.

An inclusion criterion for this study was children aged 2 to 18 years with a confirmed diagnosis of sickle cell anemia and clinical diagnosis of stroke. For those who presented with an initial stroke without a prior diagnosis of SCA, a hemoglobin electrophoresis was done to confirm sickle cell disease and provided written informed consent to participate in the study.

Sickle cell anemia children who presented with a stroke to the Sickle cell clinic were admitted to the Pediatrics wards of Mulago Hospital for management. Consent from caretakers and assent for children aged 8 to 18 years.

Procedures

Blood pressure (BP): The patient’s blood pressures were taken three times. The second and third reading was averaged to compute the patients reading. This was done using an aneroid BP machine, Fazzini, Italy with multiple child size cuffs. In this study high blood pressure was defined as a systolic BP and/or diastolic BP that is on repeated measurement, at/or above the 95th percentile [9].

Oxygen saturation (SPO2): The patients SPO2 was determined using a Nellcor™ N65 portable pulse oximeter. The reading was determined after the probe was kept on the patients’ finger for more than 1 minute.

Laboratory investigations: A complete blood count (CBC) was done using a Beckman Coulter CBC 5 Haemolyser, Beckman Coulter Inc., California, and USA. The hemoglobin electrophoresis was done using a Minicap Sebia Electrophoresis Machine, Sebia Inc., Georgia, and USA in order to verify the diagnosis of SCA in the children in the study. In addition, the level of HbF and HbS were also determined.

Statistical analysis

All data was recorded in structured questionnaires that were developed by the investigators. It included questions about the child’s current state of well being and any interventions the child may have received, This structured questionnaire was entered into a statistical software package EPI-DATA Version 3.1, (Epi-data Association, Odense, Denmark) and examined for completeness, consistency, and accuracy. The data was exported to STATA Version 10, (Stata Corp, Texas, and USA) for analysis.

The participants were recruited over a four month period from February to June 2011. They were recruited from both the SCC and the Hematology ward of Mulago Hospital.

Numerical data were summarized into means, and standard deviation for normally distributed variables; or medians and interquartile ranges for skewed data. For some continous data, we categorized them to be able to describe possible risk factors associated with stroke in our study participants.

Ethics and Consent

Permission to carry out the study was obtained from the Department of Pediatrics and Child Health; Makerere University College of Health Sciences, School of Medicine Research and Ethics Committees (SOMREC). Written informed consent was obtained from the caregivers/parents of eligible children. In addition, assent was obtained from children aged 8 years to 18 years before enrollment.

Results

We recruited 46 children with SCA stroke between February and June 2011. Forty six of these had sickle cell anemia with stroke. There were 23 (50%) males and 23 (50%) females. The median age for with SCA-related stroke was 4 years (inter-quartile range 5 to 11) years. The age distribution showed a peak of 6 years with 35% of the children below five years of age. The rest of the baseline characteristics of the children are shown in Table 1.