Visual loss caused by pseudotumor cerebri in an infant on peritoneal dialysis.

Infants with chronic renal insufficiency have multiple risk factors for developing pseudotumor cerebri (PTC) and are at particular risk for being diagnosed with PTC late, because of their inability to express symptoms. We describe a 13-month-old infant dependent on peritoneal dialysis, without evidence of central nervous system infection or inflammation, who developed acute vision loss secondary to PTC. Signs of PTC in infants include torticollis, inattentiveness, inability to track, facial paresis, or new-onset strabismus. Physicians responsible for the care of children with renal failure should be aware of the potential for PTC, as the diagnosis should be made as early as possible to prevent permanent visual loss.

Wernicke encephalopathy and beriberi during total parenteral nutrition attributable to multivitamin infusion shortage.

OBJECTIVE: Wernicke encephalopathy (WE) is an acute neurologic disorder characterized by a triad of ophthalmoplegia, ataxia, and mental confusion. WE is attributable to thiamine (vitamin B1) deficiency. Beriberi is the systemic counterpart of thiamine deficiency and often manifests in cardiovascular collapse. WE is usually associated with alcoholism and malnutrition. It has also been seen in people with gastrointestinal diseases with malabsorption. Patients who have received total parenteral nutrition (TPN) without proper replacement of thiamine have also developed WE. Since November 1996, there has been a shortage of multivitamin infusion (MVI). Many patients who were on chronic TPN with MVI ceased to receive the MVI and were converted to an oral form of the multivitamin. As a result, there have been several reports of children and adults on TPN who have developed WE as a result of thiamine deficiency. With this case report, we bring to attention the association of the MVI shortage and WE. Early diagnosis of WE is important, because if it is treated with thiamine in the acute stages, the neurologic and cardiovascular abnormalities can be reversed. CASE REPORT: We report a 20-year-old female patient with Crohn's disease who developed WE as a result of thiamine deficiency. She had Crohn's disease since age 9 years and was on chronic TPN. Two months before admission, MVI was discontinued in the TPN because of the shortage of its supply. An oral multivitamin tablet was substituted instead. She was admitted to the hospital for persistent vomiting. In the hospital, she continued to receive TPN without MVI, but continued taking an oral multivitamin preparation. Two weeks after admission, she developed signs of WE including diplopia, ophthalmoplegia, nystagmus, and memory disturbance. She also developed hypotension that was thought to be caused by beriberi. She was treated with 50 mg of intravenous thiamine. Within hours of the intravenous thiamine, her hypotension resolved. The day after the infusion, she no longer complained of diplopia, and her ophthalmoplegia had improved dramatically. Magnetic resonance imaging showed several areas of abnormally high signal on T2-weighted images in the brainstem, thalamus, and mamillary bodies. The topographic distribution of these changes was typical of WE. After 2 months, her mental status and neurologic status had recovered completely. CONCLUSION: WE and thiamine deficiency should be considered in all patients with malabsorption, malnutrition, and malignancies. WE from thiamine deficiency can occur as a result of cessation of MVI in the TPN infusion. Even if an oral multivitamin preparation is given instead of MVI, patients with malabsorption may not absorb thiamine adequately. Prompt diagnosis of WE is important because it is potentially fatal and readily treatable with thiamine supplementation. Early recognition of WE may be more difficult in children, because the classic triad of symptoms may not develop fully. Magnetic resonance imaging may be useful in these cases to confirm the diagnosis of WE. Because the shortage of MVI is expected to be a long-term, there are likely to be more cases of WE in the pediatric population of TPN-dependent children. Because there is no shortage of intravenous thiamine, it should be administered with TPN even if MVI is not available.

Assignment of the Nance-Horan syndrome to the distal short arm of the X chromosome.

There are three types of X-linked cataracts recorded in Mendelian Inheritance in Man (McKusick 1988): congenital total, with posterior sutural opacities in heterozygotes; congenital, with microcornea or slight microphthalmia; and the cataract-dental syndrome or Nance-Horan (NH) syndrome. To identify a DNA marker close to the gene responsible for the NH syndrome, linkage analysis on 36 members in a three-generation pedigree including seven affected males and nine carrier females was performed using 31 DNA markers. A LOD score of 1.662 at theta = 0.16 was obtained with probe 782 from locus DXS85 on Xp22.2-p22.3. Negative LOD scores were found at six loci on the short arm, one distal to DXS85, five proximal, and six probes spanning the long arm were highly negative. These results make the assignment of the locus for NH to the distal end of the short arm of the X chromosome likely.

Inferior oblique inclusion after lateral rectus surgery.

A retrospective and prospective study evaluated the clinical characteristics of patients with inadvertent incorporation of the inferior oblique muscle to the lateral rectus muscle after lateral rectus surgery. Nineteen cases were included in the study (12 retrospectively in the preceding 18 months and 7 during the prospective 5-month period). Thirteen cases with the inferior oblique inclusion occurred after a lateral rectus resection and 6 occurred after a lateral rectus recession. Most patients demonstrated a vertical deviation in the affected eye preoperatively. Nine had hypotropia and 8 had hypertropia. Deficient elevation in adduction in all patients was found on motility testing. After reoperation, despite freeing the inferior oblique from the lateral rectus, most patients had a persistent vertical deviation. Inadvertent inferior oblique inclusion can be avoided by inspecting the under surface of the lateral rectus and freeing any inferior oblique attachment before reattaching the lateral rectus to the globe during either resection or recession.