It has long been recognized that dyslexia often co-occurs with a range of other behavioral problems .
The present study revealed that ADHD, CD, and ODD are increasingly associated with individuals with dyslexia.
Many researches tried to study the comorbidity of ADHD in dyslexia, the results were widely variable which ranged from 18% to approximately 60%, with a median prevalence of 38.2% across studies. The prevalence of ADHD among students with dyslexia in previous studies is roughly seven times higher than the prevalence of ADHD in the general population, which is approximately 5% . These recorded figures are higher than that reported in the present study (18%).
The wide variability of ADHD prevalence across studies is most likely due to different reasons. First, children with ADHD are assessed with different clinical instruments, and ways of recruitment using different diagnostic criteria (DSM or International Classification of Disease-Tenth Revision [ICD-10]). Moreover, the prevalence of dyslexia varies across different cultures depending on the complexity of the orthographic rules .
Between the two disorders, there is a bidirectional relationship since the comorbidity is very high if one examines children with dyslexia for ADHD or children with ADHD for dyslexia. That could be explained as ADHD and dyslexia shares a common, biological etiology that is based in a genetic predisposition to both disorders. Many studies have identified specific alleles that may be associated with increased risk for both ADHD and dyslexia , and a genetic link between symptoms of ADHD and academic achievement has also been supported by twin studies . It is possible that deficits may be related to working memory and processing speed, as such difficulties are shared across ADHD and dyslexia .
In the present study, dyslexic group have high incidence of ODD (14%) than the control, also, dyslexic boys have high prevalence (14.8%) than girls (11.1%). Willcutt and Pennington, (2000b)  were on agreement with this as they reported that although dyslexia is associated with elevations of possibility of ODD in both boys and girls, this effect is stronger for boys.
On the other hand, few studies tried to identify the relation between dyslexia and comorbid CD, all of it demonstrated that learning disabilities are accompanied by personality characteristics that predispose the individual to conduct disorder .
In addition, dyslexic youth have been described by parents as having more externalizing behaviors than peers in the community and have been reported to engage in violence twice as often as non-dyslexic youth. Persistence of such problems was reflected in higher rates of antisocial personality disorder diagnoses at age 19 among males with language impairments relative to males without RD .
Also, Goldston et al. (2007)  found that disruptive behavior disorders increased markedly in poor reader than in typical reader including conduct and oppositional disorders
It may be suggested that early reading delay causally influences later tendencies to antisocial behavior as a result of a series of processes that may include lower levels of attachment to the social order and feelings of frustration or lowered self-esteem .
Impact of dyslexia on social, school, and general activities
In the present study, dyslexic individuals showed impairment in their general activities, abnormal social, and school competence.
In adolescence, dyslexic students who have a school performance comparable to the control group still show a weaker sense of school and social effectiveness, less hope, poor self-esteem, and motivation in committing to homework . In support of this, Mai Eissa, (2010)  demonstrated that dyslexia affect self-esteem negatively. It was because feeling inferior to the others’ with poor school achievement. Also, About 60% felt that their reading problems had influenced their peer relations negatively. They claimed that they had been teased or bullied because of their reading and writing difficulties.
As regards impaired school competence, it is more in girls than in boys, in the present study, it could be explained by the difference between boys and girls, in our society parents and teachers tend to value boys academic achievement more than girls so greater effort done for boys than girls. On the other hand, activities affected more in boys may be attributed to attention problems which are more common in boys that may have an impact on activities. Also increase in male disruptive manner making participation in sports and day time activities more difficult.
The relation between dyslexia and internalizing symptoms
Analysis of data show marked difference in internalizing manifestation between dyslexic and control individuals mainly in depressed–anxious manifestation but there is some gender difference as these manifestations are more in girls than boys.
These results are consistent with the study of Capozzi et al. (2007) . They found that 52% recorded a pathological score on the internalizing scale, 26.4% recorded a pathological score on the externalizing scale, and the remaining 20.5% had a pathological score on both scales, while 31.5%, obtained a pathological score on the Anxiety-Depression Scale. Lower percentages were recorded in the scales assessing somatic complaints (17.2%), withdrawal symptoms (15.5%), and thought disorders (20%).
Strong relation between dyslexia and internalizing manifestation specially anxiety among poor readers than control group was found also, in the study done by Goldston et al. (2007) .
Gender also show some difference in rating internalizing factors among children with dyslexia as in Willcutt and Pennington, (2000) . They found marked gender difference in Withdrawn and Anxious- Depressed narrow-band scales similar to the broadband findings, which made the authors suggest that dyslexia is associated more strongly with elevations in these areas in females than males.
Bryan et al. (2004) suggested a vicious circle explaining the pathology of internalizing symptoms and disorders. Starting from the sense of scarce school self-efficacy, demotivation for homework, frequent mechanisms of learned helplessness, and difficulties in social integration, dyslexic children not only experience more suffering, but risk involving in vicious circles where failure, demoralization, poor metacognitive awareness, and lack of interest for school duties grow hand in hand. Other vicious circles may add to, if not precede, the above-mentioned ones, due to probable linguistic, attention, and self-regulatory difficulties connected with deficits of social skills, that seem to appear frequently in dyslexia .
The relation between dyslexia and externalizing symptoms
The association between psychopathological symptomatic behaviors in dyslexic subjects was recorded to be 61.0% (Capozzi et al. (2007) . Also, they found that 26.4% recorded a pathological score on the externalizing scale: attention/hyperactivity subscale was in which the children’s scores most frequently fell within the clinical range. In fact, 46.5% of the sample obtained a score within the pathological range on the attention/hyperactivity scale. Only a minority of the sample obtained pathological scores on the two scales measuring aggressive and delinquent behavior (18% and 15%, respectively).
Gender also shows some difference in rating externalizing factors among children with dyslexia as in Willcutt and Pennington, (2000) study . Individuals with dyslexia exhibited higher scores than individuals from the family control group on all externalizing measures.
Although both boys and girls with dyslexia exhibited higher levels of externalizing behaviors than individuals without dyslexia, significant interactions revealed a stronger association between dyslexic aggressive behaviors among males. One hypothesis is that boys with dyslexia may be more likely to act out in a disruptive manner and will therefore be identified more frequently by parents and teachers as in need of clinical attention. In contrast, an alternative hypothesis would propose that parents and teachers tend to value male academic achievement more than female academic achievement, and consequently expend greater effort to correct reading problems in male children. The results reported here are consistent with the first hypothesis, in that boys with dyslexia tended to exhibit elevations of externalizing behaviors, whereas girls with dyslexia exhibited higher levels of internalizing symptomatology that might be less apparent to parents or teachers.
In conclusion, the present study added an evidence for the high comorbidity of ADHD, ODD, and CD with dyslexia. Also, dyslexic boys show higher rates of externalized syndromes and girls show higher rates of internalized syndromes.
Assessment of children and adolescents with speech disorders for psychiatric disorders especially ADHD and opposition defiant disorder, have to be constant part of assessment of those patients. Also attention should be directed to internalized syndromes for girls and externalized syndromes for boys. This evaluation enables the psychiatrists to manage these children appropriately.