Correspondence Address:
Dr. Anjan Dhua
Department of Pediatric Surgery, Pondicherry Institute of Medical Sciences, Puducherry - 605 014
India

Full Text

Sir,

Anti-cholinergic drugs are often used by pediatric surgeons after hypospadias operation to prevent catheter-induced bladder spasms. [1] Common known adverse effects of oxybutynin are dry mouth and constipation. Rare side-effects like acute angle closure glaucoma (ACG) are usually rare in children. We report this specific serious and potentially avoidable complication of oxybutynin.

A 9-year-old-male child was admitted for urethro-cutaneous fistula closure. He underwent single-stage urethroplasty for proximal penile hypospadias earlier at our center. His vision in the left eye was limited to "Hand movements close to face" and did not have any other complaints. At the age of 2 years he underwent keratoplasty for congenital central corneal opacity at a different center. He was on regular ophthalmological follow-up at that center. After fistula repair oxybutynin (0.2 mg/kg/dose) was started orally on the first postoperative day. Next day, the patient had recurrent episodes of vomiting and also complained of severe left retro-orbital pain and the eye was red. An ophthalmology consultation was sought. Digital tonometry revealed a stony hard eye ball. There were irregular opacities at the graft host junction present on the cornea [Figure 1]a. Oxybutynin was stopped and medical management for ACG was initiated to which he responded within 12 hours. Further evaluation showed that the patient had anterior synechiae at the previous keratoplasty site and this was responsible for a narrow angle and a shallow anterior chamber [Figure 1]b. Medical records revealed that oxybutynin was used postoperatively in his previous operation without any complication.{Figure 1}

ACG is a true ocular emergency in which the vision of the patient is at stake. A sudden massive rise in intra-ocular pressure can cause irreversible visual loss. Many urological drugs that are used systemically can have a variety of ocular side effects. [2] ACG as a specific side effect of oxybutynin was first described by Sung et al. in an elderly female patient in whom the left eye had developed ACG after administration of oxybutynin for overactive bladder. [3] Propiverine (another anti-cholinergic drug licensed in Japan) has also been incriminated for ACG in elderly patients. [4] In the literature, no more cases of anti-cholinergics causing ACG exist. This probably is because of significant awareness and a cautious approach while prescribing anti-cholinergic drugs. Kato et al.[4] showed this practice in a survey among adult urologists.

Situations that predispose children to narrow angles can co-exist with hypospadias as a part of a syndrome or in isolation. [5] In patients with shallow anterior chamber anti-cholinergic drugs are contraindicated. In our case, keratoplasty led to synechiae formation between iris and cornea leading to a narrow angle. Although oxybutynin was used after previous surgery, he remained asymptomatic possibly because the synechiae were in evolving stage. A preoperative re-evaluation by an ophthalmologist at our center possibly would have identified his predilection to ACG and avoided this complication.

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