Cerebral palsy (CP) is the most common motor disability of childhood. This hospital based study aimed at understanding the patterns and causes of CP in our locality. The results showed that 71.2% of the study population were from EL Dakahlia; however, these data can neither represent the true prevalence of CP in the district nor that there is a higher rate of CP in El Dakahlia.
It is found in our study that the male:female ratio was 1.8:1. This finding is similar to the findings in other studies, as Swedish ratio of 1.55:1 was reported . The male embryo is suggested at a greater risk of damage or death . Stillbirth, premature birth, congenital deformities, perinatal brain damage, and neonatal adverse outcomes are more common in male .
In our study, identifying risk factors was tricky due to multiple reasons. First, there are at least four health systems in Egypt (Ministry of Health, university hospitals, private sectors, and insurance hospitals), and there is no national guidelines applied for prenatal care, delivery, and management of neonatal problems. Secondly, there is lack of documentation of pregnancy, delivery, and neonatal periods. Only few neonatal care units give discharge summary for the parents about the period the baby stayed in the hospital. Thirdly, most of CP cases present to the clinics after their first birthday. Since we depended on the history given by parents, discharge, or follow-up documents (if present) in identifying risk factors, there is always the possibility that parents are uncertain about events that happened in pregnancy and delivery.
We have classified risk factors according to the time of injury into (antenatal, natal/post-natal, and post-neonatal). We have evaluated gestational age and multiple births as separate groups apart from these risk factors, and then we have identified the most common risk factors in each gestational age group.
In approximately two thirds of all children with CP in this study, a major risk factor was identified. Natal and post-natal risk factors were more predominant representing 30.5%, antenatal risk factors represent 21%, and post-neonatal represent 17.1%. No reliable risk factor could be established in 31.1% of cases. This could be explained by deficient history, reliable documents, or other risk factors that were beyond the scope of the study. However, this proportion of patients is similar to that reported in other series [35, 36].
It is found in our study that most patients (69.5%, n = 695) were born at term and this is similar to many studies. This can be explained by the fact that there is more full-term than preterm infants born at a given time .
Multiple birth is a risk factor for CP 5.4% (54 patients) with 31 patients were preterm (64.8 %) in our study. This is also found in an European study that multiple births are at < 4 times greater risk than singletons for CP data . This may be related to intra-uterine death of a triplet or a co-twin or the higher rate of prematurity [38, 39]. And also, it is related to the fertility medications and increasing age of mother .
Antenatal risk factors evaluated in this study included some of the most frequent risk factors as PROM of long duration , maternal medications (antibiotics and anti-epileptics) during pregnancy , antepartum fever , vaginal bleeding, pre-eclampsia, and CNS malformation .
In this study, CNS malformation represented 6.5% of all cases with CP. These included primary microcephaly, hydrocephaly, congenital reduction defects (holoprosencephaly), corpus callosum anomalies, and cerebellar hypoplasia. This is close to the results obtained by another study in which cerebral malformation represent 8.6% of all CP patients . Cerebral malformations can be of genetic or acquired origin. The exact pathogenesis and etiology of congenital brain malformations frequently remain unknown. However, genetic and environmental factors (toxins and infectious agents) seem to play a role .
Maternal infection suggested by (fever around delivery, prolonged rupture of membrane and documented congenital infection) represented around 6%. This is a very low percentage in comparison to other studies which reported up to 16–23% of their cases to be due to maternal infection. Both of these studies were retrospective studies evaluated maternal files for antenatal risk factors of CP [43, 47].
Maternal conditions (DM, thyroid diseases, medications during pregnancy) represented 5.4% of all CP patients in this study. This is similar to other studies [22, 48].
When evaluating antenatal risk factors in relation to gestational age, we found that CNS malformation, congenital infection, and pre-eclampsia were more common in FT. Maternal hemorrhage, prolonged rupture of membrane, maternal DM, and thyroid diseases were more significant in preterm patients. These results are similar to other studies [26, 45].
Many studies found association between CP and emergency CS . In this study, 5.8% of all CP patients were delivered by emergency CS. This was prominent with PT (51.7%) than FT (47.3%). However, we depended solely on the history from the mother and there was no explanation on why this emergency CS was done or whether the fetus had any distress before delivery or not.
Meconium aspiration occurred in 19 cases (1.9%) in this study, and all were post-term (> 42 weeks). Cord prolapsed was identified in 9 patients: 7 of them were FT and 2 were post-term. Both conditions indicate fetal distress; however, this was not supported in our study by data about fetal heart rate or cord blood PH to indicate perinatal asphyxia. The effect of amniotic fluid stained with meconium is still unclear [49, 50].
It is considered that the presence and severity of hypoxic ischemic encephalopathy during neonatal period is the strongest predictor of CP. HIE affects full term (> 37 weeks) . In this study, 8.7% (n = 87) of the babies experienced neonatal encephalopathy and 97.7% of them were FT. One study estimated HIE to be a risk factor of CP in 8–15% of term patients .
Sepsis has been proven to increase the risk of developing CP especially in preterm . In this study, sepsis in the first month of life was identified in 50 patients and 38 were preterm.
Intracranial hemorrhage in the first month of life was identified radiological in 43 patients and 26 were preterm (60%). This result is similar to other results in which 66% of preterm patients with ICH developed CP .
Kernicterus continues to be a significant problem in developing countries despite progress in the management of hyperbilirubinemia. In a clinic-based review in Nigeria, it was found that hyperbilirubinemia was the most common cause of cerebral palsy . In this study, jaundice was a major risk factor in 39 patients and 56% were FT.
When evaluating natal/post-natal risk factors in relation to gestational age, we found that certain factors are more common in certain age group. HIE, cord prolapse, and high jaundice were more predominant in FT. MAS was detected only in post-term. Emergency CS, sepsis, and intracranial hemorrhage were more common in PT.
Few studies evaluated post-neonatal risk factors; one is the SCPE follow-up study that evaluated post-neonatal risk factors in cerebral palsy patients from age 28 days to 25 months. Infection, vascular episodes, and head injury were the most common risk factors . In this study, CNS infection was identified in 59 patients, CVA in 49 patients, sepsis in 41 patients, ICH in 16 patients, and accidental injury in 6 patients. It is worth mentioning that 10 patients out of the 16 with ICH were diagnosed as late hemorrhagic disease of newborn, which is a preventable risk factor. Out of the group of the 49 patients with CVA, 16 were diagnosed with congenital cyanotic heart diseases. CNS infection and CVA were significantly more common in FT. Sepsis, ICH, and accidental injury were common in PT.
We evaluated the different risk factors collectively in relation to gestational age and that showed that patients with natal/post-natal risk factors represented 30.5% of all cases with CP and natal/post-natal risk factors were more predominant in all gestational age groups (23% of the FT, 42.9% of the PT, and 74.4% of the post-term). This is against recent studies that found antenatal risk factors to be more predominant in different gestational ages . Multiple causes may attribute to these results: (1) poor antenatal data regarding maternal pregnancy and events immediately before delivery. (2) The type of the study being a hospital based rather than population-based studies. (3) The fact that MUCH is a children hospital with a tertiary neonatal unit, referral from the unit constitutes a considerable number of patients.
Patients in this study were classified from the motor perspective into spastic (71.4%), dyskinetic (8.3%), hypotonic (9.8%), and mixed spastic with dyskinesia (10.3%). This is similar to many studies, which found that dyskinetic CP 10–20% and spastic type 80% [26, 57]. It is important to mention that some studies do not include hypotonic children as a subtype; this is due to the assumption that most hypotonic patients are believed to develop to other motor types later in their life or becomes diagnosed with other conditions that are not included under the term CP.
The spastic type of CP was the predominant motor type in the full term and preterm (72.2% and 70%). The non-spastic types are more in full term. This is similar to results by Eveline Himpens and his colleagues .
Regarding the topographic distribution of spastic and mixed patients, 45% of spastic patients had 4 limbs involvement, 31.9% had involvement of their lower limbs, and 22.8% have involvement of one side of the body (hemiplegic). Monoplegic patients (when one limb is only affected) were classified as hemiplegic. This is due to the fact that their motor, etiological, and functional behavior is the same.
Epidemiological studies have shown that topographic classification varies according to gestation. Spastic diplegia is more with preterm as in our study . It is found that spastic hemiplegia is more common in full-term babies. and this finding is similar to other studies . The proportion of spastic quadriplegia was more predominant in the term patients (79.4%) than preterm (12.7%). This is different than other studies that showed that quadriplegic CP was equal in all age groups [26, 61].
Identifying the etiologic profile of cerebral palsy types is important as each group had specific risk factors and identifying it helps understanding the potential mechanisms of pathogenesis . We found that each group exhibits a different etiologic spectrum. The spastic diplegic group had the natal/post-natal risk factors as the most common (34.7%). The dyskinetic group had more post-neonatal causes than other group. Unidentified risk factors were more predominant in the quadriplegic patients (51.3%).