Fine needle aspiration (FNA) and core needle biopsy (CNB) are recognized to be safe, useful, and inexpensive diagnostic tools for the evaluation of thyroid nodules. However, complications can arise during the procedure, albeit rarely and typically minor in nature. We report here an unusual fatal case of massive hematoma of the neck after FNA and CNB that may have caused airway obstruction. A 68-year-old Japanese woman underwent both procedures and was found dead at home later the same day. Although severe complications of FNA or CNB such as major bleeds or deaths are rarely reported, clinicians and forensic pathologists should be cognizant that complications can arise.

Recreational drugs, such as 3,4-methylenedioxymethamphetamine (MDMA) and cocaine, induce hyperthermia, which is affected by ambient temperature. 2-(4-Bromo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25B-NBOMe), a selective agonist of 5-HT_2A receptor used as a recreational drug, reportedly induces hyperthermia. This study aimed to verify whether 25B-NBOMe induces ambient temperature-dependent hyperthermia and to clarify its mechanism. Eight-week-old male Sprague-Dawley rats were administered intraperitoneal injection of 25B-NBOMe at an ambient temperature of 23°C or 29°C. 25B-NBOMe administration at 23°C did not change the core body temperature of the rats, whereas administration at 29°C induced significant hyperthermia 30-120 min post-administration. Tail surface temperature temporarily decreased 30 min post-administration, indicating heat storage by peripheral vasoconstriction despite a high ambient temperature. Because 25B-NBOMe-induced-hyperthermia was suppressed by sarpogrelate, but not by destruction of central noradrenaline or serotonin neurons, peripheral 5-HT_2A receptors were considered to contribute to the development of hyperthermia at a high ambient temperature, independently from central neurons. The temperature of brown adipose tissue (BAT) increased 60-120 min post-administration of 25B-NBOMe at 29°C, indicating thermogenesis. Previous studies have reported that peripheral serotonin contributes to the inhibition of BAT thermogenesis. Decreased plasma serotonin levels were observed at 29°C, and serotonin administration partially suppressed 25B-NBOMe-induced hyperthermia at a high ambient temperature, suggesting that decreased levels of peripheral serotonin induced BAT thermogenesis. Our findings indicate that 25B-NBOMe induces hyperthermia at a high ambient temperature via vasoconstriction regulated by 5-HT_2A receptors and BAT thermogenesis mediated by decreased levels of plasma serotonin. Thus, peripheral serotonin partially plays an important role in thermoregulation.