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Idiopathic Ductopenia in a paediatric patient: A case report and interesting clinical biochemistry
S100
PATHOLOGY 2017 ABSTRACT SUPPLEMENT
A number of labs (51%) were using QC algorithms consistent with a recently published opinion paper.1 It was also noted that 93% considered RCPAQAP allowable limits of performance when setting their QC limits. 100% of labs indicated they treated QAP samples the same as patient samples. While this survey has highlighted a number of commonalities in QC and quality practices among top performing EQA laboratories, the overall contribution to quality comes from a number of factors. Reference 1. Jones G, Calleja J, Chesher D, et al. Collective opinion paper on a 2013 AACB workshop of experts seeking harmonisation of approaches to setting a laboratory quality control policy. Clin Biochem Rev 2015; 36: 87–95.
IDIOPATHIC DUCTOPENIA IN A PAEDIATRIC PATIENT: A CASE REPORT AND INTERESTING CLINICAL BIOCHEMISTRY Richard G. Ruddell1, Christopher Burgess2,4, Tony Huynh1,3,4, Louise S. Conwell3,4, Fariha Balouch2,4, Matthew Burke1, Carel Pretorius1,4 1 Department of Chemical Pathology, Pathology Queensland Central Laboratory, Herston Hospital Campus, Herston; 2 Department of Gastroenterology, Lady Cilento Children’s Hospital, South Brisbane; 3Department of Endocrinology and Diabetes, Lady Cilento Children’s Hospital, South Brisbane; and 4School of Medicine, University of Queensland, Herston, Qld, Australia A 10-year-old male presented with a 2 week history of fevers, malaise, vomiting and erythematous rash. Progressive symptoms, cholestasis and liver injury led to liver biopsy and a diagnosis of idiopathic ductopenia. The patient demonstrated persistent hyponatraemia of uncertain aetiology that was not improved by salt supplementation or fluid restriction. The ALP-isoenzyme electrophoresis pattern demonstrated an unusual band that was consistent with the lipoprotein-ALP conjugate, lipoprotein-X. The serum appeared icteric without evidence of lipaemia and the total cholesterol concentration was 33.6 mmol/L. Pseudohyponatraemia due to the volume exclusion effect is seen in severe hypertrigliceridaemia where the sample appearance, lipaemic index or triglyceride concentration alerts the laboratory to this interference. Raised serum cholesterol is an unusual, but recognised cause of pseudohyponatraemia in patients with cholestasis.1,2 The existence of pseudohyponatraemia in our patient was confirmed with a direct ion-selective electrode method. Lipoprotein-X is found in patients with obstructive jaundice due to bile reflux into serum,2 where it contributes significantly to non-HDL cholesterol. While the pathophysiological role of lipoprotein-X remains unclear, it contributed to the apparent hyponatraemia in this case. The possibility of pseudohyponatraemia should be considered in patients with obstructive liver disease and icterus, even in the absence of hypertrigly ceridaemia. References 1. Ko GT, Yeung VT, Chow CC, et al. Pseudohyponatraemia secondary to hypercholesterolaemia. Ann Clin Biochem 1997; 34: 324–5. 2. le Riche M, Burgess LJ, Marais AD. Pseudohyponatraemia in a patient with obstructive jaundice. Clin Chim Acta 2006; 366: 357–60.
Pathology (2017), 49(S1)
QUALITY OF HYPERPARATHYROIDISM DIAGNOSIS IN INPATIENTS CHANGES WITH PTH ASSAY H. G. Schneider1,2, D. Kottahachchi1, J. Smith1, C. Chiang1, S. Joglekar1, E. Paul2, C. Bain2 1 Pathology Service, Department of Endocrinology and Department of Surgery, Alfred Health, and 2Central Clinical School, School of Public Health and Preventive Medicine and Faculty of IT, Monash University, Melbourne, Vic, Australia Hyperparathyroidism is diagnosed with elevated calcium levels and elevated parathyroid hormone (PTH) levels. We changed PTH assay [from Roche (R) to Abbott (A) in Nov 11; and back to R in Feb 14]. Both are intact PTH assays. We audited the impact of the change on the number and quality of HPT diagnoses. Information on hospital patients discharged with HPT (ICD code) was retrieved and audited by endocrinologists (Nov 2011 – Sep 2015, n = 323). The diagnosis of hyperparathyroidism was classified into categories (confirmed, likely, unlikely, secondary hyperparathyroidism). We used Student’s t-test or Wilcoxon rank-sum test, wherever appropriate. Hyperparathyroidism was more frequently diagnosed using the A-assay (26 months; 7.9 patients/month) than using the R-assay (18 months; 6.6 patients/month). Confirmed HPT was found more frequently using the R-assay (52.4 vs 34.2%, p = 0.001). Unlikely HPT (22.4 vs 11.9%, p = 0.019) and secondary HPT (18.1 vs 8.5%, p = 0.019) were found more frequently when using the A-assay. The choice of PTH assay affected the quality of the diagnosis of hyperparathyroidism. Limitations of this study include the retrospective nature and the relatively small number of patients. Clinicians should be aware of the type of PTH assay used in their laboratory and that it might affect their diagnosis. IMPROVED DENSITOMETRIC QUANTIFICATION OF bREGION PARAPROTEINS WITH HIGH-RESOLUTION GEL ELECTROPHORESIS J. D. Smith, G. I. Raines, M. Black, H. G. Schneider Clinical Biochemistry Unit, Alfred Pathology Services, Alfred Health, Vic, Australia Background: Accurate quantitation of paraprotein is essential in the diagnosis and monitoring of monoclonal gammopathies.1–3 It is recommended that paraproteins are monitored using serum protein electrophoresis (SPEP, gel or capillary) with densitometric quantification. However, quantitation of paraproteins migrating in the b-region presents an ongoing challenge for laboratories, as they may co-migrate with C3 or transferrin making their quantification by densitometry unreliable. We compared SPEP using high resolution agarose gel electrophoresis (Sebia Hydragel 15 HR) with a contemporary capillary electrophoresis system (Sebia Capillarys 2) for the detection and quantitation of paraprotein in serum samples. Methods: 222 consecutive serum samples with requests for SPEP were analysed. SPEP was performed on Sebia Hydragel 15 HR gels and capillary electrophoresis was performed on a Sebia Capillarys2 Flex piercing instrument [Protein(e) 6 kit]. Capillarys electrophoretograms were independently interpreted by two adjudicators and compared with HR SPEP interpretations and paraprotein quantification.
PATHOLOGY 2017 ABSTRACT SUPPLEMENT
A number of labs (51%) were using QC algorithms consistent with a recently published opinion paper.1 It was also noted that 93% considered RCPAQAP allowable limits of performance when setting their QC limits. 100% of labs indicated they treated QAP samples the same as patient samples. While this survey has highlighted a number of commonalities in QC and quality practices among top performing EQA laboratories, the overall contribution to quality comes from a number of factors. Reference 1. Jones G, Calleja J, Chesher D, et al. Collective opinion paper on a 2013 AACB workshop of experts seeking harmonisation of approaches to setting a laboratory quality control policy. Clin Biochem Rev 2015; 36: 87–95.
IDIOPATHIC DUCTOPENIA IN A PAEDIATRIC PATIENT: A CASE REPORT AND INTERESTING CLINICAL BIOCHEMISTRY Richard G. Ruddell1, Christopher Burgess2,4, Tony Huynh1,3,4, Louise S. Conwell3,4, Fariha Balouch2,4, Matthew Burke1, Carel Pretorius1,4 1 Department of Chemical Pathology, Pathology Queensland Central Laboratory, Herston Hospital Campus, Herston; 2 Department of Gastroenterology, Lady Cilento Children’s Hospital, South Brisbane; 3Department of Endocrinology and Diabetes, Lady Cilento Children’s Hospital, South Brisbane; and 4School of Medicine, University of Queensland, Herston, Qld, Australia A 10-year-old male presented with a 2 week history of fevers, malaise, vomiting and erythematous rash. Progressive symptoms, cholestasis and liver injury led to liver biopsy and a diagnosis of idiopathic ductopenia. The patient demonstrated persistent hyponatraemia of uncertain aetiology that was not improved by salt supplementation or fluid restriction. The ALP-isoenzyme electrophoresis pattern demonstrated an unusual band that was consistent with the lipoprotein-ALP conjugate, lipoprotein-X. The serum appeared icteric without evidence of lipaemia and the total cholesterol concentration was 33.6 mmol/L. Pseudohyponatraemia due to the volume exclusion effect is seen in severe hypertrigliceridaemia where the sample appearance, lipaemic index or triglyceride concentration alerts the laboratory to this interference. Raised serum cholesterol is an unusual, but recognised cause of pseudohyponatraemia in patients with cholestasis.1,2 The existence of pseudohyponatraemia in our patient was confirmed with a direct ion-selective electrode method. Lipoprotein-X is found in patients with obstructive jaundice due to bile reflux into serum,2 where it contributes significantly to non-HDL cholesterol. While the pathophysiological role of lipoprotein-X remains unclear, it contributed to the apparent hyponatraemia in this case. The possibility of pseudohyponatraemia should be considered in patients with obstructive liver disease and icterus, even in the absence of hypertrigly ceridaemia. References 1. Ko GT, Yeung VT, Chow CC, et al. Pseudohyponatraemia secondary to hypercholesterolaemia. Ann Clin Biochem 1997; 34: 324–5. 2. le Riche M, Burgess LJ, Marais AD. Pseudohyponatraemia in a patient with obstructive jaundice. Clin Chim Acta 2006; 366: 357–60.
Pathology (2017), 49(S1)
QUALITY OF HYPERPARATHYROIDISM DIAGNOSIS IN INPATIENTS CHANGES WITH PTH ASSAY H. G. Schneider1,2, D. Kottahachchi1, J. Smith1, C. Chiang1, S. Joglekar1, E. Paul2, C. Bain2 1 Pathology Service, Department of Endocrinology and Department of Surgery, Alfred Health, and 2Central Clinical School, School of Public Health and Preventive Medicine and Faculty of IT, Monash University, Melbourne, Vic, Australia Hyperparathyroidism is diagnosed with elevated calcium levels and elevated parathyroid hormone (PTH) levels. We changed PTH assay [from Roche (R) to Abbott (A) in Nov 11; and back to R in Feb 14]. Both are intact PTH assays. We audited the impact of the change on the number and quality of HPT diagnoses. Information on hospital patients discharged with HPT (ICD code) was retrieved and audited by endocrinologists (Nov 2011 – Sep 2015, n = 323). The diagnosis of hyperparathyroidism was classified into categories (confirmed, likely, unlikely, secondary hyperparathyroidism). We used Student’s t-test or Wilcoxon rank-sum test, wherever appropriate. Hyperparathyroidism was more frequently diagnosed using the A-assay (26 months; 7.9 patients/month) than using the R-assay (18 months; 6.6 patients/month). Confirmed HPT was found more frequently using the R-assay (52.4 vs 34.2%, p = 0.001). Unlikely HPT (22.4 vs 11.9%, p = 0.019) and secondary HPT (18.1 vs 8.5%, p = 0.019) were found more frequently when using the A-assay. The choice of PTH assay affected the quality of the diagnosis of hyperparathyroidism. Limitations of this study include the retrospective nature and the relatively small number of patients. Clinicians should be aware of the type of PTH assay used in their laboratory and that it might affect their diagnosis. IMPROVED DENSITOMETRIC QUANTIFICATION OF bREGION PARAPROTEINS WITH HIGH-RESOLUTION GEL ELECTROPHORESIS J. D. Smith, G. I. Raines, M. Black, H. G. Schneider Clinical Biochemistry Unit, Alfred Pathology Services, Alfred Health, Vic, Australia Background: Accurate quantitation of paraprotein is essential in the diagnosis and monitoring of monoclonal gammopathies.1–3 It is recommended that paraproteins are monitored using serum protein electrophoresis (SPEP, gel or capillary) with densitometric quantification. However, quantitation of paraproteins migrating in the b-region presents an ongoing challenge for laboratories, as they may co-migrate with C3 or transferrin making their quantification by densitometry unreliable. We compared SPEP using high resolution agarose gel electrophoresis (Sebia Hydragel 15 HR) with a contemporary capillary electrophoresis system (Sebia Capillarys 2) for the detection and quantitation of paraprotein in serum samples. Methods: 222 consecutive serum samples with requests for SPEP were analysed. SPEP was performed on Sebia Hydragel 15 HR gels and capillary electrophoresis was performed on a Sebia Capillarys2 Flex piercing instrument [Protein(e) 6 kit]. Capillarys electrophoretograms were independently interpreted by two adjudicators and compared with HR SPEP interpretations and paraprotein quantification.