An alternative path to the cecum: nicorandil-associated diverticular sigmoido-cecal fistula

Sigmoido-Cecal Fistula: A Rare Case of Complicated Recurrent Diverticulitis and a Review of the Literature

Patient: Female, 76

Final Diagnosis: Complicated recurrent diverticulitis

Symptoms: Abdominal pain • bloating • inability to pass stool and gas

Medication: —

Clinical Procedure: Hartmann’s procedure

Specialty: Surgery

Nicorandil, Gastrointestinal Adverse Drug Reactions and Ulcerations: A Systematic Review

INTRODUCTION

Nicorandil is a popular anti-anginal drug in Europe and Japan. Apart from some common adverse drug reactions (ADR), its safety is satisfactory. Several reports have suggested a link between nicorandil, gastrointestinal (GI) ulceration and fistulas. The review aims to critically appraise, synthesize and present the available evidence of all known GI ADR per anatomical location.

METHODS

The study complied with the PRISMA statement. Literature and pharmacovigilance databases were used to provide rate and/or calculate parameters (median age, median dose, history of symptoms, length of therapy and healing time after withdrawal of the drug). Differences in distribution of quantitative variables were analyzed via Mann-Whitney test. Correlation between quantitative variables was assessed with a Spearman's correlation coefficient. A p value <0.05 was significant.

RESULTS

Oral ulcerations occur in 0.2% of the subjects, anal ulcerations are present between 0.07% and 0.37% of patients. Oral and distal GI involvements are the most common ADR (28-29% and 27-31% of all GI ADR, respectively). The hepatobiliary system, the pancreas and salivary glands are not affected by nicorandil exposure. The time to develop oral ulcerations is 74 weeks among people on <30 mg/day compared to only 7.5 weeks in individuals on higher regimens (p = 0.47). There is a significant correlation between dose and ulcer healing time (Spearman's 0.525, p < 0.001).

CONCLUSIONS

Ulcerative disease is a very commonly reported GI ADR. A delayed ulcerative tendency supports the hypothesis of an ulcerogenic metabolite. Nicorandil seems to act as a cause of the ulcerations, but appears to also work in synergy with other promoting factors. Whether the action of the metabolites relies on a specific mechanism or a simple chemical ulceration is still to be established.

Nicorandil: from ulcer to fistula into adjacent organs

Nicorandil is an original vasodilatator used to control angina by decreasing cardiac preload and afterload. Since 1997, many reports of single or multiple nicorandil-induced ulcerations have been published. To date, eight cases of nicorandil-induced fistula into adjacent organs have been described. The pathogeneses of nicorandil-induced ulceration and fistula into adjacent organs are not yet elucidated. The two main hepatic biotransformation pathways of nicorandil are denitration and reduction of the alkyl chain leading to nicotinamide and niconitic acid which merge into the endogenous pool of nicotinamide adenine dinucleotide/phosphate. This merging which is known as saturable, may contribute to a slow and abnormal distribution of nicotinamide and nicotinic acid out of the endogenous pool. Under these special conditions, providing these two molecules in situ, nicotinic acid associated with nicotinamide may ulcerate rather recent or maintained trauma. Ulcers and fistulae induced by nicorandil heal after withdrawal. Surgical intervention is unnecessary and inappropriate as it is ineffective and exacerbates morbidity. All practitioners should be correctly informed about these serious but preventable nicorandil side effects, which mostly occur in the elderly and fragile population. In the absence of corrective measures, withdrawal of this original and active drug should be considered.