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Carbon Monoxide Poisoning in a Psychiatric Patient Mistaken for Indefinite Complaints
Miki Hamashoji1, Kotaro Kunitomo1, Taro Shimizu2
1Department of General Medicine, Kumamoto Medical Center, Kumamoto, Japan.
Introduction:
Carbon monoxide (CO) binds to haemoglobin with a much higher affinity than oxygen, forming carboxyhaemoglobin (COHb), which impairs oxygen transport and utilization. As CO concentrations can easily peak in closed environments, non-fire-related CO poisoning can also occur. However, because CO poisoning is often a nonspecific clinical finding, it can result in a diagnostic error. This report details the misdiagnosis of a 42-year-old male patient with psychiatric disorders.
Case Description:
The patient presented to the hospital with dizziness, abdominal pain and nausea on multiple occasions. His symptoms were ascribed to his psychiatric conditions. On his fifth visit, we diagnosed the patient with CO poisoning.
Discussion:
It is apparent that this patient was misdiagnosed because of his medical history, and standard analysis was overlooked. When patients with psychiatric disorders have nonspecific symptoms, it is important to check for urgent underlying conditions during diagnosis.
Learning Points:
Patients with psychiatric disorders who present with nonspecific symptoms should be evaluated for underlying conditions, including carbon monoxide poisoning.Physicians must make every effort to obtain the accurate medical history of patients with psychiatric disorders.
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