Anesthetic challenges in a child with Lowe's and Fanconi syndrome.

Oculocerebrorenal syndrome of Lowe is a rare X-linked metabolic disorder complicated by Fanconi's syndrome. Anaesthetic management of Lowe syndrome with Fanconi's syndrome is challenging to the anaesthesiologists in view of difficult airway due to microcephaly, metabolic abnormalities, and risk of peri-operative seizures. We report a successful anaesthetic management of a case of 2-year-old child scheduled for evaluation under anaesthesia following bilateral lens aspiration surgery.

Oculocerebrorenal syndrome of Lowe (OCRL) is a rare (1:500,000), X-linked recessive disorder with multisystem involvement.[1] It is characterized by a classic triad of congenital cataract, neonatal or infantile hypotonia, and renal tubular dysfunction.[1] This syndrome is complicated by association with Fanconi's syndrome.[2] We herein report a case of 2-year-old child scheduled for evaluation under anaesthesia following bilateral lens aspiration surgery. Written informed consent to publish this case report was obtained from the child's parents.

Anaesthetic management of patient with Lowe's syndrome for eye surgery is challenging due to associated problem of anticipated difficult airway, metabolic abnormalities, risk of convulsions, fragile bones, and need to prevent rise in intraocular pressure.

A 2-year-old child (6 kg, head circumference 40 cm, below 3rd percentile) diagnosed with Lowe's syndrome presented with bilateral cataract since birth. He underwent bilateral lens aspiration surgery 2 months back, which was apparently uneventful but anaesthetic records were unavailable. On preanaesthetic evaluation, he was found to be born out of a nonconsanguinous marriage as a full term by normal vaginal delivery at home, with no associated maternal perinatal complications. He had delayed milestones and failure to gain weight. On general examination, he was found to have microcephaly with plagiocephaly, microphthalmos, floppy posture, and rickety rosary. He had prominent facial veins, sparse hair, thin skin, abnormal eye movement, and bilateral clinodactyly [Figure 1]. He had thin skin and prominent veins on both upper and lower limbs. There was no history of involuntary movements or seizures, but deep tendon reflexes were sluggish in all the four limbs.

Figure 1

Child with Lowe's syndrome: microcephaly, plagiocephaly, and microphthalmos

His vital parameters (heart rate, blood pressure) and systemic examination were within normal limits. His blood investigations showed low haemoglobin (4 g/dl), microcytic hypochromic red blood cells (RBCs) with anisopoikilocytosis, and raised alkaline phosphatase (785 IU/l). His serum Na+ was 128 mEq/l, K+ 3.42 mEq/l, Ca2+ 8.4 mg/dl, PO43− 1.7 mg/dl, and lactate 2.6 mmol/l. Urinary albumin was present. Arterial blood gas analysis showed a pH of 7.39, PCO2 25.7, PO2 130, and HCO3 15.3. X-ray showed rachitic changes in both wrists [Figure 2]. Renal ultrasound did not show any evidence of nephrocalcinosis or nephrolithiasis. Thyroid profile was normal.

Figure 2

X-ray wrist showing rachitic changes

The low haemoglobin was corrected by transfusing packed RBCs and oral iron supplementation. Additionally, the child was treated with potassium, magnesium, calcium, phosphate, and bicarbonate supplementation. After 2 weeks, blood investigations improved with Hb of 7.9 g/dl, serum Na+ 143.6 mEq/l, K+ 3.42 mEq/l, Ca2+ 8.8 mg/dl, PO43− 2.1 mg/dl, and lactate 1.6 mmol/l.

After ensuring preoperative fasting of 4 h to breast milk, 2 h to clear fluids, child was scheduled as the first case. The monitors were applied as per American Society of Anesthesiologist standard guidelines (heart rate, blood pressure, oxygen saturation, capnography, respiratory rate). His baseline vital parameters were: heart rate 160/min; blood pressure 70/48 mm Hg, respiratory rate 18/min, and oxygen saturation 99% on room air. Paediatric difficult airway cart with all the adjuvants and alternatives to laryngoscopy and supraglottic airway devices was kept ready. Inhalational induction using 8% sevoflurane with 100% oxygen was done and a 24 G intravenous cannula was secured on left dorsum of hand. Size 1.5 Ambu Aura 40 (Ambu Inc., USA) laryngeal mask airway was inserted and anaesthesia was maintained with sevoflurane 2–2.5% and 50% oxygen in air (1.0–1.2 minimum alveolar concentration) with pressure support ventilation (pressure support 10 cm of H2O and trigger of 1 l/min) using Drager Primus. 1% Dextrose in ringer lactate with total of 30 ml was given intraoperatively. The intraoperative course was uneventful.

Multiorgan manifestations are attributed to OCRL gene, which encodes inositol polyphosphate 5-phosphatase. It is involved in endocytic trafficking and actin skeleton dynamics.[2] Lowe syndrome involves eyes (congenital cataracts, glaucoma with buphthalmos, corneal keloid), nervous system (muscle hypotonia, intellectual disability, seizures, behavioral abnormalities), and the kidneys (renal Fanconi syndrome features such as proximal tubular dysfunction, low-molecular-weight proteinuria, aminoaciduria, hypercalciuria/nephrocalcinosis, phosphaturia). Hypotonia, proteinuria are apparent at birth, while manifestations such as incomplete renal Fanconi syndrome, growth retardation, development delay, and renal tubular dysfunction are recognized later.[2] Clinical problems typically include polyuria, acidosis, and renal phosphate wasting, leading to the development of renal rickets, osteomalacia, and pathological fractures, and eventually end-stage renal disease.[2] These patients require surgical interventions for lens extraction, glaucoma, scoliosis correction, dental surgery, orchidopexy, gastrostomy.[2],[3]

Our anaesthetic concerns in this patient were difficult airway, risk of convulsions, electrolyte and acid–base imbalance, hypotonia, and hypoglycaemia.[3] We anticipated difficult ventilation in this child due to microcephaly with risk of airway obstruction and thus, we opted for inhalational induction with sevoflurane, preserving the spontaneous breathing of the patient. We chose sevoflurane for induction due to normal calcium levels and absence of seizures, which we would have otherwise avoided as sevoflurane should be avoided in patients with verified clinical epileptic activity.[4] Normalization of electrolytes such as potassium, magnesium, calcium, phosphate, and bicarbonate supplementation should be targeted prior to elective surgery. Dextrose in ringer lactate should be given intraoperatively for prevention of hypoglycaemia and dehydration. Rachitic changes and demineralization should be treated with oral phosphate supplements and vitamin D as was done in this patient. Proper patient positioning is needed to prevent injury to rickety bones.

Lowe's syndrome is a chronic debilitating disease wherein adequate preoperative evaluation, airway adjuncts, normalization of electrolytes, prevention of hypoglycaemia, and careful positioning is needed for successful management.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.