Carbamazepine Induced Thrombocytopeniapatient

Abstract

A 40-year-old male presented to the Out Patient Department of Oral Medicine with one week history of toothache. He was diagnosed with a tooth ailment for which he was advised tooth extraction. He was referred to the Department of Medicine in view of polycythemia and thrombocytopenia. The patient is a known case of cyanotic congenital heart disease. He also gave history of brain abscess 16 years ago which was surgically drained. During that admission, patient was started on AEDs. He was lost to follow up for the last 16 years but has continued to take the AEDs regularly. The last known attack of seizures were six years prior to present admission, which the patient attributed to missed doses of medication.He was on phenobarbitone and carbamazepine at the time of cur rent admission. On examination, the patient had features of chronic hypoxia like grade 3 clubbing and central cyanosis. The lab para meters showed polycythaemia, which was expected, but the patient also had thrombocytopenia that could not be explained by his clinical condition. His 2D echocardiogram was suggestive of congenitally corrected transposition of great arteries with a severe pulmonary stenosis and a large ventricular septal defect mimicking the fallot physiology along with AV/VA discordance. The patient was evaluated for the cause of thrombocytopenia and carbamazepine, which is known to cause haematological alterations, was considered as a possibility. The Naranjo algorithm was applied and a score of 7 was suggestive of a probable association ofcarbamazepine to the thrombocytopenia. The drug was discontinued on day 3 of hospital stay. On admission his platelets were 45,000/cu.mm along with presence of giant forms. After cessation of drug, one week later, the platelet count showed a significant improvement to 82,000 platelets/cu.mm.The patient was taken up for tooth extraction and was given a course of amoxicillin and clavulunate. Patient's AEDs were optimised; levetericetam and phenobarbitone were prescribed at weight adjusted dosages. Patient also underwent multiple phlebotomy procedures for polycythaemia. At the time of discharge, the platelet count returned to normal levels, 1.21 lacs platelets/cu.mm. The Keywords: Antiepileptic drugs, Cyanotic congenital heart disease, Haematological alterations abstRaCt Antiepileptic Drugs (AEDs) are commonly associated with haematological disorders, including anaemia, thrombocytopenia, neutropenia and even bone marrow failure. Fatal disorders like aplastic anaemia are uncommon. On exploring through the literature, older AEDs are more associated with haematological alterations than newer AEDs, and careful monitoring is warranted especially with phenytoin, carbamazepine and valproate. The exact cause of these alterations is not established, though immune mechanisms and pharmacology of individual drugs are the proposed mechanisms, a further research along this path is underway. Of worth mentioning here, this predilection of older AEDs towards haematological disorders is pronounced in children compared to a...

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Perampanel-Induced, New-Onset Thrombocytopenia in a Patient With Refractory Seizures: A Case Report

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“…In head-to-head trials, no ASM has proven more efficacious than is CBZ, in the treatment of focal epilepsy [6][7][8][9][10]. Having withstood the test of time, CBZ remains a first line ASM to treat focal epilepsy [28] with a widely known AE profile [11,[14][15][16][17][18][19][20][21][22]26,27]. Twice-daily regimen, using the controlled release formulation [44], has proven efficacious and avoids prescribing a midday dosage, which is often overlooked by the most diligent of patients.…”

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