Guanidinoacetate methyltransferase (GAMT) deficiency diagnosed by proton NMR spectroscopy of body fluids.

In patients with guanidinoacetate methyltransferase (GAMT) deficiency several parameters may point towards the diagnosis of GAMT deficiency. These include the low levels of creatine and creatinine in urine, the high concentration of guanidinoacetic acid (GAA) in urine and the low levels of creatine and creatinine in the cerebrospinal fluid (CSF). In this study, body fluids from 10 GAMT deficient patients were analysed using (1)H NMR spectroscopy. The urine 1D (1)H NMR spectra of all the patients showed a doublet resonance at 3.98 ppm (pH 2.50) derived from GAA present in high concentration. For this compound, a good recovery and good correlation was found between an LC-MS/MS method and (1)H NMR spectroscopy. In CSF NMR spectra of these patients, the singlet resonances of creatine and creatinine (3.05 and 3.13 ppm, respectively) were absent (normally always present in (1)H NMR spectra of CSF). Due to overlap by other resonances, the doublet of GAA could not be observed. Our data demonstrate that (1)H NMR spectroscopy of urine and CSF can be used to diagnose patients with GAMT deficiency.

Surface contamination of chemotherapy drug vials and evaluation of new vial-cleaning techniques: results of three studies.

PURPOSE: The results of three studies that describe the external contamination of chemotherapy drug vials are presented. New techniques for the improved decontamination of vials containing cisplatin are also described. SUMMARY: Study 1 evaluated the external contamination of drug vials with cyclophosphamide and ifosfamide in a pharmacy setting. Widespread contamination of the outside of drug vials was found with each drug. Study 2 evaluated the surface contamination of drug vials with cyclophosphamide and fluorouracil in three pharmacies. Sporadic contamination with fluorouracil was detected, while cyclophosphamide was found on most vials. In study 3, investigators compared the decontamination abilities of a standard decontamination procedure at the manufacturer level with an improved decontamination procedure and the use of sleeves to further decrease contamination. Though the methods of each study reported herein differed, the outcomes were similar. All chemotherapy drug vials studied demonstrated levels of contamination with the drug well above the limit of detection. Improved decontamination procedures, combined with the use of protective sleeves, reduced the level of platinum contamination by 90%, suggesting that standard decontamination procedures should be reconsidered. CONCLUSION: The results of these studies are consistent with several others that have reported contamination of the outside surface of drug vials for a number of chemotherapy drugs. Contamination can be reduced by using decontamination equipment and protective sleeves during the manufacturing process.