Mefloquine-induced trigeminal sensory neuropathy

Oral-maxillofacial adverse events related to antimalarials

Malaria is a worldwide parasitic disease, which affects millions of lives every year. Various medications are recommended by WHO for prevention and treatment of malaria. However, adverse events caused by antimalarials were frequently reported, some of which were severe and fatal. Disorders of many organs related to antimalarials have been well recognized, whereas few studies concentrated on the relationship between antimalarials and oral-maxillofacial system health. Current review generalized the relevance of antimalarials to the health of oral-maxillofacial part and raised an urgent need to form a standard management for antimalarial-related oral-maxillofacial adverse events.

Adverse Drug Reactions in the Orofacial Region

A wide spectrum of drugs can sometimes give rise to numerous adverse orofacial manifestations, particularly dry mouth, taste disturbances, oral mucosal ulceration, and/or gingival swelling. There are few relevant randomized double-blind controlled studies in this field, and therefore this paper reviews the data from case reports, small series, and non-peer-reviewed reports of adverse drug reactions affecting the orofacial region (available from a MEDLINE search to April, 2003). The more common and significant adverse orofacial consequences of drug therapy are discussed.

Malaria Prevention, Mefloquine Neurotoxicity, Neuropsychiatric Illness, and Risk-Benefit Analysis in the Australian Defence Force

The Australian Defence Force (ADF) has used mefloquine for malaria chemoprophylaxis since 1990. Mefloquine has been found to be a plausible cause of a chronic central nervous system toxicity syndrome and a confounding factor in the diagnosis of existing neuropsychiatric illnesses prevalent in the ADF such as posttraumatic stress disorder and traumatic brain injury. Overall health risks appear to have been mitigated by restricting the drug's use; however serious risks were realised when significant numbers of ADF personnel were subjected to clinical trials involving the drug. The full extent of the exposure, health impacts for affected individuals, and consequences for ADF health management including mental health are not yet known, but mefloquine may have caused or aggravated neuropsychiatric illness in large numbers of patients who were subsequently misdiagnosed and mistreated or otherwise failed to receive proper care. Findings in relation to chronic mefloquine neurotoxicity were foreseeable, but this eventuality appears not to have been considered during risk-benefit analyses. Thorough analysis by the ADF would have identified this long-term risk as well as other qualitative risk factors. Historical exposure of ADF personnel to mefloquine neurotoxicity now also necessitates ongoing risk monitoring and management in the overall context of broader health policies.

Numb Chin Syndrome

"Numb chin syndrome" (NCS) refers to new-onset numbness of the lower lip and chin within the distribution of the mental or inferior alveolar nerves. While this focal numbness may be downplayed or even overlooked by patients and clinicians, in the right clinical scenario this may be the presenting symptom of an underlying malignancy. In the absence of any obvious, temporally related dental cause, there are certain conditions that clinicians should consider including orofacial and systemic malignancies as well as several inflammatory disorders. Thorough diagnostic evaluation should always be performed when no clear cause is evident. This paper will discuss the differential, recommended evaluations, and the prognosis, for a patient presenting with NCS.

Idiosyncratic quinoline central nervous system toxicity: Historical insights into the chronic neurological sequelae of mefloquine

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Regulators now warn adverse neurological effects from mefloquine may be irreversible.

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Many neurological effects resemble those of a common quinoline CNS toxidrome.

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The quinoline toxidrome is associated with a risk of CNS neuronal degeneration.

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CNS neuronal degeneration may underlie some neurological effects from mefloquine.

Mefloquine is a quinoline derivative antimalarial which demonstrates promise for the treatment of schistosomiasis. Traditionally employed in prophylaxis and treatment of chloroquine-resistant Plasmodium falciparum malaria, recent changes to the approved European and U.S. product labeling for mefloquine now warn of a risk of permanent and irreversible neurological sequelae including vertigo, loss of balance and symptoms of polyneuropathy. The newly described permanent nature of certain of these neurological effects challenges the conventional belief that they are due merely to the long half-life of mefloquine and its continued presence in the body, and raises new considerations for the rational use of the drug against parasitic disease. In this opinion, it is proposed that many of the reported lasting adverse neurological effects of mefloquine are consistent with the chronic sequelae of a well characterized but idiosyncratic central nervous system (CNS) toxicity syndrome (or toxidrome) common to certain historical antimalarial and antiparasitic quinolines and associated with a risk of permanent neuronal degeneration within specific CNS regions including the brainstem. Issues in the development and licensing of mefloquine are then considered in the context of historical awareness of the idiosyncratic CNS toxicity of related quinoline drugs. It is anticipated that the information presented in this opinion will aid in the future clinical recognition of the mefloquine toxidrome and its chronic sequelae, and in informing improved regulatory evaluation of mefloquine and related quinoline drugs as they are explored for expanded antiparasitic use and for other indications.

Idiopathic trigeminal sensory neuropathy. A case report

Idiopathic trigeminal sensory neuropathy is a rare clinical condition characterized by sensory disturbances on the face. Its symptoms may be permanent or temporary and a wide variety of diagnostic procedures is usually required to establish the diagnosis. Frequently, it is the first manifestation of a systemic disorder. In the majority of cases causal treatment is not possible, even though patients with trigeminal sensory neuropathy should be carefully monitored by physicians.

Case report: Peripheral polyneuropathy and mefloquine prophylaxis

We describe a case of a woman who developed a peripheral polyneuropathy shortly after completing 4 weekly doses of mefloquine hydrochloride (250 mg) malaria prophylaxis. Although mefloquine-related central nervous system neuropathy is well described in the literature, peripheral polyneuropathy similar to this case has been documented only once before, to our knowledge.

Trigeminal sensory neuropathy and facial contact dermatitis due to Anthurium sp

BACKGROUND

Trigeminal sensory neuropathy (TSN) describes a heterogeneous group of disorders manifesting as facial numbness.

OBJECTIVE

We report the case of a patient who had TSN associated with contact dermatitis due to Anthurium sp.

METHOD/RESULTS

A 21-year-old female patient developed left hemifacial contact dermatitis after exposure to the anthurium plant. The patient had paresthesias and pain in the V2 and V3 divisions of the left trigeminal nerve. Eight days after its onset the dermatitis resolved, but numbness developed in the V2 and V3 divisions of the left trigeminal nerve. Cranial CT scan and MRI, as well as CSF and extensive work-up exams, were normal. After one month the symptoms disappeared completely.

CONCLUSION

Anthurium sp, an indoor ornamental plant that contains calcium oxalate crystals, and can causes contact dermatitis. To our knowledge, this is the first report associating TSN with contact dermatitis due to Anthurium sp.

Mefloquine toxicity presenting with polyneuropathy - a report of two cases in India

We report two cases of people from different states in India who developed polyneuropathy following intake of mefloquine for treatment of malaria. To the best of our knowledge this has not been reported before.