Service evaluation of radiographer-led vetting and protocoling of Computed Tomography (CT) scan requests in a Singapore public healthcare institution.

INTRODUCTION: A service improvement project involving the vetting and protocoling of Computed Tomography (CT) scan requests by qualified CT radiographers was initiated in 2018. AIM: This study provides a comprehensive evaluation of how a radiographer-led initiative aims to ensure that the CT scan requests received by the Radiology department are clinically appropriate, which in turn will reduce interruptions to the interpretation and reporting of imaging examinations by radiologists, who might otherwise be required to attend to clinically inappropriate and wrongly protocolled CT scan requests. METHOD: Outpatient CT scan requests received from July to October 2021 were vetted and protocolled by a qualified CT-trained radiographer for parameters which included the appropriateness of the clinical indication, adequacy of patient preparation for the scan, as well as the suitability of the requested examination protocol pertaining to the need for contrast media, multiple contrast-enhanced imaging phases, and the appropriateness of the scan range. RESULTS: Poor patient preparation and insufficient or inaccurate clinical indications were the most common findings during the vetting process (71%). Out of the 64 CT scan requests with protocol errors, 77% were attributed to contrast media type errors. The odds of incorrect CT scan requests increased with the requesting clinician's rank, while there was no such significant correlation with the clinical specialty of the requesting clinician or the CT scan type. CONCLUSION: The meticulous vetting of imaging requests helps to ensure that limited imaging hardware resources are allocated to more clinically appropriate cases, correct protocols are applied to requested imaging scans, and that patients undergoing imaging are adequately prepared, thereby enhancing overall patient care. IMPLICATIONS FOR PRACTICE: Vetting of imaging requests by radiographers, who are capable to make appropriate clinical decisions related to their enhanced level of practice ensures patient safety and optimisation of Radiology resources.

Hidrotic ectodermal dysplasia: study of a large Chinese pedigree.

Hidrotic ectodermaldysplasia was found, to our knowledge, for the first time in a Chinese family in Malaysia, and it affected 15 members in five generations. The disease, which is transmitted as a non-sex-linked autosomal dominant trait, presumably originated from southern China. All 15 members had the typical nail, hair, and skin lesions, and we observed three different types of nail defects. Scalp alopeica was more extensive in the female members while keratoderma of the palms and soles was more notable in the male members. The nail and skin lesions also became severer with age. Except for the infectious eczematoid dermatitis present in the propositus, none had other skin or systemic disorders. All were relatively healthy and had normal life expectancies;

Distinct organ-dependent mechanisms for the control of murine cytomegalovirus infection by natural killer cells.

Antiviral mechanisms by which natural killer (NK) cells control murine cytomegalovirus (MCMV) infection in the spleens and livers of C57BL/6 mice were measured, revealing different mechanisms of control in different organs. Three days postinfection, MCMV titers in the spleens of perforin 0/0 mice were higher than in those of perforin +/+ mice, but no elevation of liver titers was found in perforin 0/0 mice. NK cell depletion in MCMV-infected perforin 0/0 mice resulted only in an increase in liver viral titers and not in spleen titers. Depletion of gamma interferon (IFN-gamma) in C57BL/6 mice by injections with monoclonal antibodies to IFN-gamma resulted in an increase of viral titers in the liver but not in the spleen. Analyses using IFN-gamma-receptor-deficient mice, rendered chimeric with C57BL/6 bone marrow cells, indicated that in a recipient environment where IFN-gamma cannot exert its effects, the depletion of NK cells caused an increase in MCMV titers in the spleens but had little effect in the liver. IFN-gamma has the ability to induce a variety of cells to produce nitric oxide, and administrating the nitric oxide synthase inhibitor N(omega)-monomethyl-L-arginine into MCMV-infected C57BL/6 mice resulted in MCMV titer increases in the liver but not in the spleen. Taken together, these data suggest that in C57BL/6 mice, there is a dichotomy in the mechanisms utilized by NK cells in the regulation of MCMV in different organs. In the spleen NK cells exert their effects in a perforin-dependent manner, suggesting a cytotoxic mechanism, while in the liver the production of IFN-gamma by NK cells may be a predominant mechanism in the regulation of MCMV synthesis. These results may explain why the Cmv-lr locus, which maps closely to genes regulating NK cell cytotoxic function, confers an NK cell-dependent resistance to MCMV infection in the spleen but not in the liver.

Arsenic poisoning from anti-asthmatic herbal preparations.

Arsenic poisoning, a disease of the past, was recently found in 74 patients in Singapore over a 15-month period. Most victims (70%) had a chronic form of poisoning and 64% of the cases were caused by a local anti-asthmatic herbal preparation containing 12,000 ppm of inorganic arsenic sulphide. The other patients were poisoned by six other brands of herbal preparations used for the treatment of asthma and a variety of other illnesses. Subsequent investigations revealed another 22 other brands of Chinese herbal preparations containing high concentrations of inorganic arsenic ranging from 25 to 107,000 ppm, of which most were imported. Nearly 40% of the patients had taken the medicine for less than six months, but the others had a longer history of exposure ranging from one to 15 years. Systemic involvement was confined mainly to the skin (91%), nervous system (51%), gastrointestinal system (23%) and blood (23%). Malignancy of the skin was present in six patients, and of the visceral samples, toxicological confirmation was found in half of the cases investigated. There was no correlation between the clinical status of the patients and their tissue arsenic content. The importance of arsenic poisoning by herbal preparations is discussed, as there are no known reports of their association.