Browsing by Subject "Clinical Pathology"

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    Open Access
    Assessment of the effectiveness of electronic gatekeeping as a utilization management tool at Groote Schuur Hospital
    (2018) Bosman, Michelle; van der Watt, George; Omar, Fierdoz; Vreede, Helena
    BACKGROUND: Utilization management ensures the appropriateness of laboratory testing by reducing the performance of tests which can be reasonably avoided with no adverse effects for the patient. Electronic gatekeeping, a utilization management tool, was introduced at Groote Schuur in 2010. Criteria were based on the minimum retesting interval, healthcare location, level of experience and discipline of the requesting clinician and specific ICD-10 codes. METHODS: A retrospective observational study assessing the effectiveness of electronic gatekeeping at Groote Schuur Hospital (Cape Town, South Africa), by comparing the test request volumes by using absolute test numbers and pre-defined ratios in the year prior to gatekeeping, to the two years following implementation. A secondary aim is to apply selected ratios to the other national academic hospitals to determine the potential for cost saving. RESULTS: At the medical wards of Groote Schuur Hospital there was an overall decrease in number and cost of tests of 24% per inpatient day for 2011. The most dramatic difference in cost is seen for chloride (91%) followed by HbA1c (90%), FT3 (89%) and CRP (82%). The application of ratios to Groote Schuur Hospital show a decrease in 2011 in all ratios apart from PCT: FBC+WCC (0.003 vs 0.002) and Mg: Ca (0.86 vs 0.84). AST: ALT remained the same at 0.55. This suggests overall effectiveness of the eGK rules although there is ongoing panel requesting. If the GSH eGK rules were to be applied at all other national academic hospitals, it could translate into a potential cost saving of $13 411 873.96 (R103 196 838.80) per annum. CONCLUSIONS: Electronic gatekeeping is an effective utilization management tool at Groote Schuur Hospital. It is relatively easy to implement and manage, and when combined with additional tools has the potential to result in larger reductions of unnecessary tests, cost savings and improved patient outcome.
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    Open Access
    Investigation of an atypical protoporphyric family in South Africa
    (2010) Haumann, Carel Eduard; Meissner, Peter
    Affected members of the family investigated in this dissertation presented with photosensitivity and raised red cell protoporphyrin concentrations, indicative of protoporphyria. Further examination of this family revealed features that were atypical of erythropoietic protoporphyria. These included a highly penetrant disease, disease severity as expressed by more prevalent hepatic complications, a preponderance of protoporphyrin in its zinc chelated form, a therapeutic response to iron supplementation, and an absence of mutations in the ferrochelatase gene or haplotype markers associated with erythropoietic protoporphyria. We have reviewed clinical data from this family, established a ferrochelatase enzyme assay in our laboratory, and shown normal ferrochelatase enzyme activity in affected subjects.
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    Open Access
    Utility of chloride and adenosine deaminase measurement in cerebrosphinal fluid for the early presumptive diagnosis of tuberculous meningitis
    (2017) Swanepoel, Hendré; Wojno, Justyna Maria; Omar, Fierdoz
    Background: Chloride and adenosine deaminase measurements in cerebrospinal fluid are still sporadically requested as part of tuberculous meningitis work-up. In the literature, evidence is contradictory and opinion is divided on their utility in clinical practice. The accuracy of both for the early presumptive diagnosis of tuberculous meningitis was investigated in patients in a region with high prevalence of tuberculosis and HIV infection in order to inform a decision on whether to continue offering these tests to clinicians. Methods: A retrospective descriptive study of diagnostic accuracy was conducted at the National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa. Data were collected on all cerebrospinal fluid specimens submitted for tuberculosis culture between 1 January 2012 and 31 December 2014. Chloride and adenosine deaminase concentrations were compared with automated liquid culture for Mycobacterium tuberculosis as the reference standard. Findings: There were 2531 cerebrospinal fluid specimens submitted for tuberculosis culture during the study period; exclusion of duplicates yielded 2081 specimens. Chloride was requested on 711 (34·2%) specimens; 44 (6·2%) were tuberculosis culture-positive. Adenosine deaminase was requested on 152 (7·3%) specimens; 20 (13·2%) were culture-positive. Chloride sensitivity (<120 mmol/L) for the detection of tuberculous meningitis was 93·2% (95% confidence interval 81·3-98·6), with specificity 62·4% (58·6-66·1), positive predictive value 14% (10·3-18·6), negative predictive value 99·3% (97·9-99·9), positive likelihood ratio 2·48 (2·18-2·81), and negative likelihood ratio 0·109 (0·037-0·326). Adenosine deaminase sensitivity (>6 U/L) was 70% (45·7-88·1), specificity 89·4% (82·8-94·1), positive predictive value 50% (30·6-69·4), negative predictive value 95·2% (89·8-98·2), positive likelihood ratio 6·6 (3·72-11·7), and negative likelihood ratio 0·336 (0·171-0·657). Interpretation: In this patient population chloride and adenosine deaminase showed at best only modest performance as markers of tuberculous meningitis. However, very good negative predictive values could serve to identify patients highly unlikely to have the disease.