Metallosis Presenting as a Progressive Neurologic Deficit Four Years After a Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis: A Case Report.

STUDY DESIGN: A case report. OBJECTIVE: The aim of this study was to report a case of progressive pain and paraparesis secondary to metallosis four years after a pediatric posterior spinal fusion (PSF). SUMMARY OF BACKGROUND DATA: Metallosis as a late complication of pediatric spinal surgery is rarely reported. Myelographic computed tomography (CT) can be helpful in establishing the diagnosis. The use of serum chromium levels as a means of definitive diagnosis has been suggested, but has only been reported retrospectively. METHODS: A 19-year-old male presented four years after PSF for adolescent idiopathic scoliosis with sudden onset of pain and neurologic deficits. Radiographs and CT scan suggested infection. Intraoperatively, no purulent material was noted, but black and yellowish corrosive debris was found around the right L1 pedicle screw, so it was removed and the cavity packed with tobramycin impregnated calcium sulfate beads. After surgery, neurologic deficits worsened. CT myelogram showed irregular opacification of the thecal sac at the level of the conus. A posterior laminectomy and decompression was performed with removal of all debris and spinal instrumentation. Metallosis within the spinal canal was noted and serum chromium levels were obtained. RESULTS: The patient was discharged one week after admission with improvement of pain and gradual improvement in neurologic examination. Three years postdischarge, the patient is asymptomatic and examination shows bilateral clonus. Serum chromium levels declined from a high of 4.5 µg/L operatively to 0.8 at final follow-up (normal: 0.2-0.6 µg/L). CONCLUSION: Although uncommon, metallosis should be considered in the differential diagnosis of any late presenting case of pain, infection-like symptoms, or neurologic deficits after pediatric PSF. CT myelography and serum chromium levels may help guide diagnosis; however, surgical exploration is needed for definitive diagnosis and treatment. LEVEL OF EVIDENCE: 4.

S100ß in heavy metal-related child attention-deficit hyperactivity disorder in an informal e-waste recycling area.

Exposure to lead even at low levels correlates with attention-deficit/hyperactivity disorder (ADHD). However, lead-contaminated environments are often contaminated with other heavy metals that could exacerbate lead-induced ADHD. We conducted this study to evaluate the relationship between multiple heavy metals and child behaviors, and the involvement of S100 calcium-binding protein ß (S100ß) expression in child ADHD in Guiyu, an internationally-known e-waste contaminated recycling town. Two hundred and forty kindergarten children, 3- to 7-years of age, who lived in Guiyu, were recruited for this study. Child behavioral assessment was derived from parent and teacher ratings. Serum S100ß was assayed by an enzyme-linked immunosorbent assay (ELISA). Lead (Pb), cadmium (Cd) and manganese (Mn) levels in whole blood were measured using graphite furnace atomic absorption spectrometry (GFAAS). The prevalence of children with ADHD symptoms in Guiyu was 18.6%, with the percentage of children suspected to have behavior problems being 46.2% or 46.5%, based on the Rutter parents' or teachers' scale scores, respectively. Child blood levels of Pb, Cd, and Mn correlated with certain behavioral abnormalities, such as conduct problems and antisocial behavior. Serum S100ß levels were associated with heavy metal levels in blood, and certain behavioral abnormalities. These findings suggest that exposure to various environmental heavy metals in Guiyu might result in child behavior disorders. Results also indicate that S100ß may provide information for laboratory evaluation of neurotoxicity.

Self-reported neurological clinical manifestations of metal toxicity in metal-on-metal hip arthroplasty.

Adverse reactions to metal particle debris have been increasingly reported as a complication following large head metal-on-metal (MoM) hip arthroplasty. Elevated metal ion levels are a cause for concern. The aim of this study is to evaluate whether exposure to cobalt is associated with patient characteristics and symptoms of neuropathy, representing nervous system dysfunction. A cross-sectional study was conducted comparing patients with a MoM total hip arthroplasty and patients with a conventional hip arthroplasty. They received three questionnaires, one to assess neurotoxic complaints and two standardised self-administered questionnaires to identify symptoms that are suggestive of peripheral neuropathy. Current and historical data were available for whole blood cobalt levels in all patients. We analysed potential predictive factors for cobalt based on five different cut-off levels (0-2, 2-4, 4-10, 10-20, >20 µg/L). We performed 723 MoM total hip arthroplasties in 643 patients in our clinic. The response rate was 89%. Male-female ratio was 236/280, median age 63.6 years (30-72) with a mean follow-up of 50.6 months (20-86). We also sent the questionnaires to 98 patients in the control group. An increase in the incidence of reported symptoms was not consistent with higher serum cobalt levels. Female gender was the only consistent predictive factor for serum cobalt at different cobalt cut-off levels in the multivariate analysis. The study population did not show an increase in reported symptoms with elevated cobalt levels. Neurotoxic symptoms and whole blood cobalt levels did not show a consistent relationship with different dichotomised levels of cobalt exposure.

[Clinical and epidemiological peculiarities of multiple sclerosis in patients with different level of essential and toxic chemicals in blood serum].

Multiple sclerosis as it seen presently is a disease determined by the interaction of genetic and environmental factors. Risk factors are some chronic infections and living in ecological hazard areas. In this aspect, the authors review a role of metals which remains unclear so far. The paper presents the data on the effects of zinc, cadmium, lead and copper on the multiple sclerosis course.

Blood levels of toxic and essential metals in motor neuron disease.

Toxic and essential metals have been implicated in the pathogenesis of sporadic motor neuron disease (SMND), but attempts to measure blood levels of these metals have led to contradictory results. We, therefore, measured blood levels of various metals using paired SMND/controls. In 20 subjects with SMND (15 males, five females, mean age 56.8 years) and 20 partner controls (15 females, five males, mean age 55.0 years) cadmium, lead, mercury, copper, zinc and selenium levels were measured in blood, plasma and red cells with inductively coupled plasma mass spectrometry and manganese levels with atomic absorption spectrophotometry. Results were analysed using non-parametric tests. Hypo-osmotic red blood cellfragility was estimated in six SMND/control pairs to see if hemolysis could account for increased metal levels. The plasma cadmium level was significantly raised in SMND cases (P = 0.005), but with considerable overlap between SMND and controls. No other metal levels were significantly different, though plasma lead in SMND had a tendency to be higher than controls. No difference in red cell fragility was found between groups. In conclusion, plasma levels of cadmium were raised in this SMND group, but the biological significance of this is uncertain. The measurement of metals in the blood of SMND cases seems unwarrranted for routine diagnostic testing.