A Case of Solitary Pseudo-Ainhum of the Right 4th Toe at the University Clinic of Dermatology-Venereology of the Hubert Koutoukou Maga National University Hospital Center in Cotonou

¹University Clinic of Dermatology-Venereology of CNHU-HKM / Cotonou, Benin

²Buruli Ulcer Screening and Treatment Center of Allada, Benin

³Faculty of Health Sciences of Cotonou, Benin

⁴Faculty of Medicine, University of Lubumbashi, Democratic Republic of the Congo

^*Corresponding author: Pierre Kitha Bitingo, University Clinic of Dermatology-Venereology of CNHU-HKM / Cotonou, Benin, Faculty of Health Sciences of Cotonou, Benin & Faculty of Medicine, University of Lubumbashi, Democratic Republic of the Congo, Tel : 00229 55 68 56 56, Emails: [email protected]; [email protected]

Received Date: March 08, 2025

Published Date: March 24, 2025

Citation: Kitha P, et al. (2025). A Case of Solitary Pseudo-Ainhum of the Right 4^th Toe at the University Clinic of Dermatology-Venereology of the Hubert Koutoukou Maga National University Hospital Center in Cotonou. Mathews J Dermatol. 9(1):27.

Copyrights: Kitha P, et al. © (2025).

ABSTRACT

Pseudoainhum is a rare congenital or acquired disease characterized by progressive fibrous constriction of the fingers and/or toes, leading to their amputation. Ainhum is an idiopathic disease that primarily affects the fifth toe of Black individuals, mainly in tropical regions. It was a 42-year-old female patient who came for consultation regarding a light-colored patch on the right 4th toe, which had been progressively evolving for five years. The lesion was initially pruritic, followed by ulceration and subsequent deformation of the toe. There was no significant medical history. On physical examination, a circular constriction groove was observed at the interphalangeal joint of the right 4^th toe, dividing it into two parts, held together by a thin, non-tender fibrous band. Several etiological hypotheses have been proposed for pseudo-ainhum, all leading to the same outcome-toe amputation-if appropriate management is not provided in a timely manner.

Keywords: Pseudo-Ainhum, Solitary, Cotonou.

INTRODUCTION

Pseudoainhum is a rare congenital or acquired disease characterized by progressive fibrous constriction of the fingers and/or toes, leading to their amputation. Ainhum is an idiopathic disease that primarily affects the fifth toe of Black individuals, mainly in tropical regions. Based on the experience of five cases and a review of the literature, the authors describe the clinical characteristics of these diseases and analyze various etiological hypotheses, including infectious (fungal infections, mycobacteria), traumatic (plants), vascular, neurological (polyneuritis), and genetic mechanisms (keratoderma) [1-3].

We report a case of solitary pseudoainhum of the right 4^th toe in Cotonou, Benin.

Observation

It was a 42-year-old female patient who came for consultation regarding a light-colored patch on the right 4^th toe, which had been progressively evolving for five years. The lesion was initially pruritic, followed by ulceration and subsequent deformation of the toe. There was no significant medical history.

On physical examination, a circular constriction groove was observed at the interphalangeal joint of the right 4^th toe, dividing it into two parts, held together by a thin, non-tender fibrous band (Figures 1 & 2).

Figure 1. Circular constriction of the interphalangeal joint of the 4^th toe.

Figure 2. Non-tender filiform band on the plantar aspect of the right 4^th toe.

Given this presentation of a painless circular constriction of the right 4^th toe, the diagnosis of solitary pseudo-ainhum of the right 4^th toe was established. No further investigations were conducted. The patient was referred to the trauma department for further management.

Argument

Our case is notable because the pseudo-ainhum affects only a single toe in an individual with no history of congenital keratodermas, certain systemic diseases, diabetes, or alcoholism, as described in the literature [2-5]. This condition has no racial predilection and should be distinguished from ainhum, which specifically affects the 5th toe in Black individuals [6]. Several etiopathogenic hypotheses have been proposed, including infectious, traumatic, neurological, vascular, and genetic factors [7]. Some associations were being described like with CREST syndrome, epidermolytic ichthyosis [1,2].

CONCLUSION

Several etiological hypotheses have been proposed for pseudo-ainhum, all leading to the same outcome-toe amputation-if appropriate management is not provided in a timely manner.

ACKNOWLEDGEMENTS

None.

CONFLICTS OF INTEREST

None.

REEFERENCES

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