Kynurenine, Kynurenic Acid, Quinolinic Acid and Interleukin-6 Levels in the Serum of Patients with Autism Spectrum Disorder.

Background and Objectives: It is known that inflammatory processes play a role in the pathogenesis of autism spectrum disorder (ASD). It is also reported that immune activation induces the kynurenine pathway (KP), as known as the tryptophan destruction pathway. In our study, we aimed to investigate whether the serum levels of KP products and interleukin (IL)-6 activating indolamine 2-3 dioxygenase (IDO) enzyme are different in healthy developing children and children with ASD. Materials and Methods: Forty-three ASD children aged 2-9 were included in this study. Forty-two healthy developing children, similar to the patient group in terms of age and gender, were selected as the control group. Serum levels of kynurenic acid, kynurenine, quinolinic acid and IL-6 were analyzed using the ELISA method. ASD severity was evaluated with the Autism Behavior Checklist (ABC). Results: The mean age of children with ASD was 42.4 ± 20.5 months, and that of healthy controls was 48.1 ± 15.8 months. While the serum levels of kynurenic acid, kynurenine and interleukin-6 were higher in the group with ASD (p < 0.05), there was no significant difference (p > 0.05) in terms of the quinolinic acid level. There was no significant difference between the ABC total and subscale scores of children with ASD and biochemical parameters (p > 0.05). Conclusions: We conclude that these biomarkers must be measured in all ASD cases. They may be important for the diagnosis of ASD.

The Effect of Methylphenidate on the Hearing of Children with Attention Deficit Hyperactivity Disorder

Abstract Introduction There has been a sudden idiopathic hearing loss case presented after methylphenidate treatment in a child with attention deficit hyperactivity disorder (ADHD). Objective This study was performed to reveal the probable ototoxic side effects of methylphenidate use in patients with ADHD. Methods Thirty pediatric patients with ADHD were included in the study. Pure tone audiometry, speech discrimination scores, waves I, III, V absolute latencies and waves IIII, I-V, III-V interpeak latencies at the 80 dB nHL intensity after click stimulus auditory brainstem response (ABR) results were compared before and 3 months after methylphenidate treatment. Results There were no statistically significant difference between pretreatment and posttreatment pure tone and speech audiometry findings and ABR results (p > 0.05 for all parameters). Conclusion Methylphenidate can be regarded as a safe drug regarding ototoxic side effects. Additional studies with a larger sample size and longer follow-up may be needed.

Neuroleptic Malignant Syndrome Associated with Valproate in an Adolescent.

Neuroleptic malignant syndrome (NMS) is a life-threatening idiosyncratic reaction that usually occurs after the administration of antipsychotic drugs. Antidepressants, benzodiazepines, and antiepileptic drugs are also suggested to be associated with NMS. It is believed to result from a dopaminergic blockade in the central nervous system. NMS is manifested by hyperthermia, muscle rigidity, autonomic dysfunction, altered mental status, leukocytosis, and elevated serum creatinine phosphokinase. Valproate is commonly used in the treatment of many psychiatric and neurologic disorders. Valproate can precipitate NMS, especially when used with antipsychotic drugs concurrently. A 17-year-old male patient, who presented with fever, muscular rigidity, confusion, sweating, and tachycardia was admitted to the emergency room. He had been taking only valproate for the last two months for bipolar disorder. His laboratory analyses revealed raised serum hepatic enzymes, creatinine phosphokinase, and myoglobin levels. Considering fever, rigidity, autonomic dysfunction, cognitive alteration, and high creatinine phosphokinase levels, the patient was diagnosed with NMS. In this paper, we aim to discuss the association between valproate and NMS.