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Urethral keratosis caused by vitamin A deficiency: two case reports
Shinsuke Yoshizawa1, Kensuke Ohashi2, Tetsuro Sugihara2
1Department of Pediatric Urology, Saitama Children's Medical Center, 1-2, Shintoshin, Chuo- ku, Saitama, 330-8777, Japan. crossingtherubicon1201@yahoo.co.jp.
Background:
Dysuria in children can have various etiologies, including ureteric stones, phimosis, congenital obstructive posterior urethral membrane, and neurogenic bladders. However, there have been no reports of vitamin A deficiency (VAD) causing dysuria due to urethral keratosis. Here, we report two cases of urethral keratosis caused by a VAD.
Case Presentation:
An 8-year-old boy (Patient 1) and a 6-year-old boy (Patient 2) presented with multiple episodes of dysuria and epididymitis. Both patients had intellectual disabilities and autism, which prevented voiding cystourethrography. Therefore, the patient was admitted for cystoscopy under general anesthesia. Cystoscopy revealed urethral diastolic dysfunction and a large amount of desquamated epithelium obstructing the urethra in both patients, causing urinary obstruction and dysuria. Catheterization was repeated; however, the symptoms recurred after catheter removal. Although the cause of recurrent urinary obstruction could not be initially identified, an ophthalmologist found Bitot's spots and suggested the possibility of a VAD. Serum vitamin A levels were extremely low in both patients, leading to the diagnosis of urethral keratosis due to VAD. VAD can be attributed to an unbalanced diet resulting from intellectual disabilities or autism. Vitamin A replacement therapy improved both the urethral symptoms and cystoscopic findings.
Conclusion:
Dysuria due to VAD is extremely rare, and urethral keratosis as a cause of dysuria is likely the first report of its kind worldwide. VAD may develop due to an unbalanced diet in patients with intellectual disabilities or autism. Therefore, it is essential to consider VAD as a potential cause of dysuria in patients with intellectual disabilities and autism.
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