Association between bone characteristics and cardiovascular risk factors among adults in selected urban areas in Selangor, Malaysia.

INTRODUCTION: Cardiovascular disease and osteoporosis (OP) have been shown to have similar risk factors but studies have demonstrated contradictory results with regards to their associations. This study evaluated relationships between bone characteristics and cardiovascular risk factors among adults in selected urban areas in Malaysia. MATERIALS AND METHODS: A cross-sectional study was performed involving 331 subjects between 45-90 years recruited at a health screening programme. Sociodemographic and clinical characteristics were recorded. Biochemical analyses on fasting blood samples and dual energy X-ray absorptiometry scan to determine bone mineral density (BMD) were performed. RESULTS: Increased waist circumference (WC) was protective for abnormal BMD status (osteopenia and OP). Males with increased high-density lipoprotein cholesterol (HDL) were more likely to be osteoporotic. WC, fasting blood glucose (FBG) and triglyceride (TG) were positively associated with BMD at all sites but was gender specific. In contrast, WC was negatively associated with trabecular bone score (TBS) for females but this association became attenuated when adjusted for fat percentage. HDL and MetS were negatively and positively associated with BMD, respectively in males. CONCLUSION: The cardiovascular risk factors of raised WC, FBG, TG and low HDL were significantly associated with increased BMD with skeletal site and gender specific differences after adjusting for confounders. However, a higher WC was associated with a weaker skeletal microstructure reflected by lower TBS in females driven by fat percentage. A higher BMD was demonstrated among MetS individuals. These findings suggest that adiposity may have a protective effect on BMD.

Survey on serum protein electrophoresis and recommendations for standardised reporting.

INTRODUCTION: Serum protein electrophoresis (SPE) is a well-established laboratory technique. However, reporting of results varies considerably between laboratories. The variation in reporting can cause confusion to the clinician with a potential of adversely impacting patient care. The purpose of the survey was to find out the variation in reporting and to prepare recommendations to the Malaysian laboratories based on the survey to reduce both the variation in reporting between laboratories and the risk of misinterpretation of reports. MATERIALS AND METHODS: To determine the extent of variation in reporting of protein electrophoresis results questionnaires were distributed to the pathologists of various laboratories in Malaysia regarding the method, quantification of paraprotein concentrations and immunoglobulin assays, and information regarding current laboratory electrophoresis practices. RESULTS: Variation was found in the following reporting practices: (a) screening protocol; (b) reporting of serum albumin; (c) numerical reporting of protein fractions and paraprotein; (d) co-migration of a paraprotein with a normal serum protein; (e) reporting of multiple paraprotein bands (f) appearance of small abnormal band and oligoclonal bands and (g) communication about of interferences. CONCLUSION: The pathologists of the country made recommendations on the reporting of protein electrophoresis. Harmonised reporting will reduce inconsistency, variation in reporting, improve the quality of the report and most importantly improve patient care.

A national audit of estimated glomerular filtration rate and proteinuria and the MACD CKD task force recommendations.

INTRODUCTION: The Malaysian Association of Clinical Biochemists (MACB) established a Task Force for Chronic Kidney Disease. A survey was undertaken by the Task Force on the reporting of estimated glomerular filtration rate (eGFR) and urine albumin by hospital laboratories in Malaysia in both the government and private sectors. MATERIALS AND METHODS: An e-mail invitation to participate in an online survey was sent to hospital laboratories in Malaysia (n=140). Questions regarding methods for measuring creatinine, equations for calculating eGFR, eGFR reporting, the terminology used in reporting urine albumin, types of samples and the cut-off values used for normal albuminuria. RESULTS: A total of 42/140 (30%) laboratories answered the questionnaire. The prevalent method used for serum creatinine measurement was the Jaffé method (88.1%) traceable to isotope-dilution mass spectrometry. eGFR was reported along with serum creatinine by 61.9% of laboratories while 33.3% of laboratories report eGFR on request. The formula used for eGFR reporting was mainly MDRD (64.3%) and results were reported as exact numbers even when the eGFR was <60 ml/min/1.73m2. The term microalbumin is still used by 83.3% of laboratories. There is a large heterogeneity among the labs regarding the type of sample recommended for measuring urine albumin, reference interval and reporting units. CONCLUSION: It is evident that the laboratory assessment of chronic kidney disease in Malaysia is not standardised. It is essential to provide a national framework for standardised reporting of eGFR and urine albumin. Recommendations developed by the MACB CKD Task Force, if adopted by all laboratories, will lead to a reduction in this variability.

Screening for phaeochromocytoma in patients with acute cerebrovascular disease: Is it necessary?

INTRODUCTION: Phaeochromocytoma may present with uncontrolled hypertension leading to haemorrhagic stroke (HS), ischaemic stroke (IS) and transient ischaemic attack (TIA). False elevation in the levels of CATS/ METS has been reported in acute cerebrovascular disease. Our aim was to analyse the frequency and pattern of elevations of CATS/METS in patients with acute cerebrovascular disease and to determine associated factors. MATERIALS AND METHODS: This is a retrospective study of 112 samples of CATS/ METS received by the laboratory over a two-year period, from patients with acute cerebrovascular disease. CATS/METS were measured using LC/MS/MS method. Clinical details and CATS/METS level were obtained from the database. Mann-Whitney U test and Kruskal Wallis test were used for statistical analysis. These statistical analyses were performed using SPSS v.20.0 (IBM Corp., Armonk, NY, USA). RESULTS: Of the 112 patients, 39% had HS, 54% had IS and 7% had TIA. A total of 29% of patients had elevated CATS/ METS. Elevated levels of CATS/METS were noted in 41% and 25% of HS and IS patients, respectively (p=0.53). Median norepinephrine, epinephrine and metanephrine levels in HS were significantly higher than IS (p< 0.05). Systolic blood pressure was higher in those who had elevated CATS/ METS (p=0.04). Only for two patients with elevated CATS/METS repeat testing was performed. Age, diastolic blood pressure and the time of sample collection in relation to the presentation, for CATS/METS were not significantly different between groups that had elevated levels of CATS/ METS versus those who did not. CONCLUSION: We noted that CATS/METS were elevated in one-third of patients, especially in patients with high systolic blood pressure. Increase in CATS/METS should be appropriately followed up with repeat testing. Since false elevation in CATS/METS has been reported in cerebrovascular disease, screening for phaeochromocytoma is best deferred for a month.

Acute Intermittent Porphyria: A rare cause of hyponatraemia.

INTRODUCTION: Hyponatraemia is one of the most frequent laboratory findings in hospitalised patients. We present an unusual case of hyponatraemia in a 23-year-old female secondary to acute intermittent porphyria (AIP), a rare inborn error of metabolism. CASE REPORT: The patient presented with upper respiratory tract infection, fever, seizures and abdominal pain. An initial diagnosis of encephalitis was made. In view of the unexplained abdominal pain with other clinical findings such as posterior reversible encephalopathy syndrome by CT brain, temporary blindness as well as hyponatraemia, acute intermittent porphyria was suspected. Urine delta aminolaevulinic acid (δ-ALA) and porphobilinogen were elevated confirming the diagnosis of AIP. Genetic studies were done for this patient. The patient had a complete resolution of her symptoms with carbohydrate loading and high caloric diet. CONCLUSION: Although rare, AIP should be considered as a cause of hyponatraemia in a patient who presents with signs and/or symptoms that are characteristic of this disease.

Establishing the cut off values of androgen markers in the assessment of polycystic ovarian syndrome.

INTRODUCTION: Hyperandrogenism remains as one of the key features in Polycystic Ovarian Syndrome (PCOS) and can be assessed clinically or determined by biochemical assays. Hirsutism is the most common clinical manifestation of hyperandrogenism. The clinical assessment is subjected to wide variability due to poor interobserver agreement and multiple population factors such as ethnic variation, cosmetic procedures and genetic trait. The difficulty in resolving the androgen excess biochemically is due to a lack of consensus as to which serum androgen should be measured for the diagnosis of PCOS. The aim of the study was to compare and establish the diagnostic cut off value for different androgen biomarker for the diagnosis of PCOS. MATERIALS AND METHODS: A total of 312 patients classified to PCOS (n = 164) and non PCOS (n = 148) cohorts were selected from the Laboratory Information System (LIS) based on serum total testosterone (TT) and sex hormone binding globulin (SHBG) from the period of 1st April 2015 to 31st March 2016. PCOS was diagnosed based on Rotterdam criteria. Clinical hyperandrogenism and ultrasound polycystic ovarian morphology were obtained from the clinical records. The other relevant biochemical results such as serum luteinizing hormone (LH), follicle stimulating hormone (FSH) and albumin were also obtained from LIS. Free androgen index (FAI), calculated free testosterone (cFT) and calculated bioavailable testosterone (cBT) were calculated for these patients. Receiver Operating Characteristic (ROC) curve analysis were performed for serum TT, SHBG, FAI, cFT, cBT and LH: FSH ratio to determine the best marker to diagnose PCOS. RESULTS: All the androgen parameters (except SHBG) were significantly higher in PCOS patients than in control (p<0.0001). The highest area under curve (AUC) curve was found for cBT followed by cFT and FAI. TT and LH: FSH ratio recorded a lower AUC and the lowest AUC was seen for SHBG. cBT at a cut off value of 0.86 nmol/L had the highest specificity, 83% and positive likelihood ratio (LR) at 3.79. This is followed by FAI at a cut off value of 7.1% with specificity at 82% and cFT at a cut off value of 0.8 pmol/L with specificity at 80%. All three calculated androgen indices (FAI, cFT and cBT) showed good correlation with each other. Furthermore, cFT, FAI and calculated BT were shown to be more specific with higher positive likelihood ratio than measured androgen markers. CONCLUSIONS: Based on our study, the calculated testosterone indices such as FAI, cBT and cFT are useful markers to distinguish PCOS from non-PCOS. Owing to ease of calculation, FAI can be incorporated in LIS and can be reported with TT and SHBG. This will be helpful for clinician to diagnose hyperandrogenism in PCOS.

Severe asymptomatic hypophosphataemia in a child with T-acute lymphoblastic leukaemia.

Hypophosphataemia is a metabolic disorder that is commonly encountered in critically ill patients. Phosphate has many roles in physiological functions, thus the depletion of serum phosphate could lead to impairment in multiple organ systems, which include the respiratory, cardiovascular, neurological and muscular systems and haematological and metabolic functions. Hypophosphataemia is defined as plasma phosphate level below 0.80 mmol per litre (mmol/L) and can be further divided into subgroups of mild (plasma phosphate of 0.66 to 0.79 mmol/L), moderate (plasma phosphate of 0.32 to 0.65 mmol/L) and severe (plasma phosphate of less than 0.32 mmol/L). The causes of hypophosphataemia include inadequate phosphate intake, decreased intestinal absorption, gastrointestinal or renal phosphate loss, and redistribution of phosphate into cells. Symptomatic hypophosphataemia associated with haematological malignancies has been reported infrequently. We report here a case of asymptomatic severe hypophosphataemia in a child with acute T-cell lymphoblastic leukaemia. A 14-year-old Chinese boy was diagnosed to have acute T cell lymphoblastic leukaemia (ALL). His serum biochemistry results were normal except inorganic phosphate and lactate dehydrogenase levels. The serum inorganic phosphate level was 0.1mmol/L and the level was low on repeated analysis. The child had no symptoms related to low phosphate levels. The possible causes of low phosphate were ruled out and urine Tmp/GFR was normal. Chemotherapy regime was started and the serum phosphate levels started to increase. Hypophosphataemia in leukaemia was attributed to shift of phosphorus into leukemic cells and excessive cellular phosphate consumption by rapidly proliferating cells. Several reports of symptomatic hypophosphataemia in myelogenous and lymphoblastic leukaemia in adults have been reported. To our knowledge this is the first case of severe asymptomatic hypophosphataemia in a child with ALL.

Causes of Low HbA1c in Malaysian University Hospital.

INTRODUCTION: Glycohemoglobin (HbA1c) most accurately reflects the previous two to three months of glycaemic control. HbA1c should be measured regularly in all patients with diabetes, and values should be maintained below 7% to prevent the risk of chronic complications. Apart from the genetic variants of haemoglobins many other conditions also known to affect HbA1c measurements. In this study we evaluated the conditions that cause low HbA1c results. METHODS AND MATERIALS: The data was collected retrospectively HbA1c was measured in our laboratory by Biorad Variant II turbo 2.0. The method is based on chromatographic separation of HbA1c on a cation exchange cartridge. This method has been certified by National Glycohemoglobin Standardization Programme (NGSP). 58437 requests were received in a period of one year (January to December 2011). Medical records were reviewed to identify the conditions that might be associated with these low values. RESULTS: Among 58437 samples analysed, 53 patients had HbA1c levels < 4.0%. Fourteen patients had haemoglobinopathy. In 34 patients without Hb variants had conditions such as chronic liver disease, chronic kidney disease, haemolytic anaemia, pregnancy, and anaemia of chronic disease. Five non-pregnant individuals who were screened for diabetes mellitus had HbA1c levels < 4%. CONCLUSION: Our study underscores the importance of that both laboratories and the physicians should be aware of the factors that can influence the HbA1c results. The haematological status should be taken into consideration for proper interpretation of HbA1c results.

Importance of screening for macroprolactin in all hyperprolactinaemic sera.

INTRODUCTION: Prolactin (PRL) exists in different forms in human serum. The predominant form is monomeric PRL (molecular mass 23 kDa) with smaller amounts of big PRL (molecular mass 50-60 kDa) and at times macroprolactin (molecular mass 150-170 kDa). Macroprolactin, generally considered to be biologically inactive, accounts for the major part of prolactin in some patients. Different immunoassays for prolactin differ in reactivity with this macromolecular complex. AIM: The present study was undertaken to assess the incidence of macroprolactinaemia in our cohort of hyperprolactinemic patients. METHOD: 204 samples with hyperprolactinemia were evaluated for macroprolactinemia by polyethylene glycol (PEG) precipitation and gel filtration chromatography (GFC). Recoveries ≤60% after PEG precipitation were considered to have macroprolactinaemia. RESULTS: A total of 43 (21%) of these patients had less than 60% recovery after PEG precipitation. GFC confirmed that in seven of these patients macroprolactin was the major part of the prolactin. Recoveries were < 40% PEG precipitation in these samples. Combined macro and hyperprolactinemia was observed in two samples and the recovery after PEG precipitation was >40% but ≤50%. The incidence of macroprolactinemia in our cohort of hyperprolactinaemic patients was noted to be 4.4%. CONCLUSION: Macroprolactin is a significant cause of misdiagnosis, unnecessary investigation, and inappropriate treatment and hence it is useful to screen all patients with high PRL levels with PEG precipitation and to apply GFC to samples with recoveries <50%.

Modification to reporting of qualitative fluorescent spot test results improves detection of glucose-6-phosphate dehydrogenase (G6PD)-deficient heterozygote female newborns.

INTRODUCTION: The glucose-6-phosphate dehydrogenase (G6PD) fluorescent spot test (FST) is a useful screening test for G6PD deficiency, but is unable to detect heterozygote G6PD-deficient females. We sought to identify whether reporting intermediate fluorescence in addition to absent and bright fluorescence on FST would improve identification of mildly deficient female heterozygotes. METHODS: A total of 1266 cord blood samples (705 male, 561 female) were screened for G6PD deficiency using FST (in-house method) and a quantitative enzyme assay. Fluorescence intensity of the FST was graded as either absent, intermediate or normal. Samples identified as showing absent or intermediate fluorescence on FST were analysed for the presence of G6PD mutations using TaqMan@SNP genotyping assays and direct nucleotide sequencing. RESULTS: Of the 1266 samples, 87 samples were found to be intermediate or deficient by FST (49 deficient, 38 intermediate). Of the 49 deficient samples, 48 had G6PD enzyme activity of ≤ 9.5 U/g Hb and one sample had normal enzyme activity. All 38 intermediate samples were from females. Of these, 21 had G6PD activity of between 20% and 60%, and 17 samples showed normal G6PD activity. Twenty-seven of the 38 samples were available for mutation analysis of which 13 had normal G6PD activity. Eleven of the 13 samples with normal G6PD activity had identifiable G6PD mutations. CONCLUSION: Glucose-6-phosphate dehydrogenase heterozygote females cannot be identified by FST if fluorescence is reported as absent or present. Distinguishing samples with intermediate fluorescence from absent and bright fluorescence improves detection of heterozygote females with mild G6PD deficiency. Mutational studies confirmed that 85% of intermediate samples with normal enzyme activity had identifiable G6PD mutations.

RET-Y and RBC-Y in the diagnosis of iron deficiency associated with anaemia of inflammation.

We evaluated the usefulness of RET-Y and RBC-Y in distinguishing functional iron deficiency from iron-deficiency anaemia (IDA) in patients with anaemia of inflammation (AI). Sixty healthy blood donors constituted the control group. We studied RET-Y and RBC-Y in 115 patients with hypochromic/microcytic anaemia. Of these 42 patients had uncomplicated IDA and 73 had AI. The AI patients were further subdivided into AI with IDA and AI with functional IDA based on soluble transferrin receptor (sTfR) levels. The mean RBC-Y and RET-Y values in iron-deficient patients were 122.4 and 119.8, respectively, which were significantly lower than the control (P < 0.001). The mean level of RET-Y in patients with AI associated with IDA was 149.3 and this level in AI patients with functional iron deficiency was 147.4. RET-Y levels in both subgroups of AI patients were significantly lower than control but no significant difference was observed between the two subgroups. Similar findings were observed for RBC-Y. Receiver operating characteristic analysis also showed lower specificity for RBC-Y and RET-Y compared with that of sTfR and its log ferritin ratio (F-index). RET-Y and RBC-Y are useful in the diagnosis of simple IDA but have limited utility in the diagnosis of IDA with AI.

RBC-Y/MCV as a discriminant function for differentiating carriers of thalassaemia and HbE from iron deficiency.

Individuals with alpha-thalassaemia (ATT), beta-thalassaemia (BTT) and HbE trait (HET) are often initially identified based on haematological parameters. However, the values of these parameters usually overlap with iron deficiency anaemia (IDA) and anaemia of chronic disease (ACD). We evaluated the use of RBC-Y in 156 normal individuals and 332 patients; ATT (n = 37), BTT (n = 61), HET (n = 25), HbH disease (n = 5), ACD (n = 67), IDA (n = 83) and ACD with IDA (n = 54). Diagnostic efficiency was analysed by receiver operating characteristics (ROC). MCH was better compared with RBC-Y in discriminating normal from abnormal with sensitivity and specificity of 94% at a cut-off of 26 pg. The Green and King (G&K) index performed the best in discriminating carriers from IDA and ACD with area under the ROC curve (AUC(ROC)) of 0.81. However, if ACD was excluded, RBC-Y/MCV was a good discriminator for carriers from IDA with AUC(ROC) = 0.845. In general screening of populations with ATT, BTT and HET, we propose that hypochromic individuals be first identified by MCH <26 pg and carriers distinguished within these hypochromic individuals from IDA by using RBC-Y/MCV. However, if the prevalence of ACD were high within the screening population, G&K index would be a more suitable discriminator.

The utility of immature reticulocyte fraction as an indicator of erythropoietic response to altitude training in elite cyclists.

Altitude training is sometimes employed by elite endurance athletes to improve their sea level performance. This improvement results from the increased red cell mass consequent upon the boost in erythropoietin (EPO) level that occurs as a response to the relatively hypoxic environment at high altitudes. We measured serum EPO levels together with various red cell and reticulocyte parameters including immature reticulocyte fraction (IRF) in eight national track-endurance cyclists, resident at sea-level, prior to and upon return from an altitude of approximately 1905 m. Reticulocytes and soluble transferrin receptor (sTfR) were significantly increased with reduction in ferritin levels immediately on return from high altitude indicating increased erythropoietic activity. IRF in particular showed a significant peak immediately on return but decline to sub-baseline levels by day 9, and recovery to baseline by day 16. Our results indicate that IRF is a sensitive marker of erythropoietic status in athletes undergoing altitude training and subsequent loss of EPO stimuli on return to sea level.

Use of red blood cell indices for the identification of iron deficiency among blood donors.

The objective of this study was to identify haematological parameters useful in screening for iron deficiency among blood donors. Iron deficiency is a common complication of blood donation and often goes unrecognized until anaemia develops. Biochemical markers such as soluble transferrin receptor (TfR), ferritin and log(TfR/F) have been proposed as more valid indicators of body iron status. Red blood cell (RBC) parameters are, however, more easily measured and have also been proposed as indicators of iron depletion. We measured ferritin and TfR in 192 blood donors together with RBC analysis, performed on two haematology analysers. Thirteen donors had parameters suggestive of haemoglobinopathy and were excluded from further analysis. Overall, 10% (18/179) of the remaining donors had iron deficiency, as defined by log(TfR/F) exceeding the 95th percentile of the value in the population of first-time donors. Using receiver operating characteristic analysis, the sensitivity of ferritin was 100%, with a specificity of 90% at a cut-off of 15 mug L(-1). The sensitivity and specificity of RBC-Y at a cut-off of 152 for detecting iron deficiency were 81 and 89%, respectively. Haemoglobin content of reticulocytes, meanwhile, showed sensitivity of 69% and specificity of 93% when a cut-off of 28 pg was used. Both measures compare favourably with haemoglobin which only showed a sensitivity of 50%, although specificity was 91% at a cut-off value of 125 g L(-1). The parameter RBC-Y can be useful as a screening measure for iron deficiency in blood donors.

Serum soluble transferrin receptor in hypochromic microcytic anaemia.

INTRODUCTION: The objective of this study was to assess the clinical significance of soluble transferrin receptor (sTfR) in hypochromic microcytic anaemia. METHODS: Serum sTfR was determined on 91 blood samples with haemoglobin less than 110 g/L and MCV less than 76 fl or MCH less than 27.0 pg. The samples were classified as iron deficiency anaemia (IDA), anaemia of chronic disease (ACD) and thalassaemia. ACD was further divided into groups 1 and 2, based on the serum ferritin level. RESULTS: The sTfR level in the control was 1.53+/-0.8 mg/L. In IDA, the sTfR level was 5.53+/-8.76 mg/L and this was significantly higher compared with the control (p-value is less than 0.0001). sTfR levels in ACD (3.32+/-3.94 mg/L) and the thalassaemia group(1.64+/-1.02 mg/L) were not significantly different from that of the control (p-value is more than 0.05). In ACD, the sTfR level in group 1 was significantly higher when compared with the control (p-value is less than 0.001) and group 2 (p-value is less than 0.01). A significantly higher sTfR/ferritin ratio was observed in IDA (2,368.98+/-7,236.4 microg/microg) compared to the control (37.6+/-43.7 microg/microg) (p-value is less than 0.001). No significant difference was noted between ACD, thalassaemia and control (p-value is greater than 0.05). sTfR/ferritin ratio was significantly higher in group 1 of ACD when compared with that of control and group 2 (p-value is less than 0.001). CONCLUSION: Serum sTfR and sTfR/ferritin ratio are useful parameters in hypochromic microcytic anaemia to diagnose iron deficiency particularly when associated with chronic inflammation. sTfR can be done selectively in ACD patients when ferritin levels are more than 60 microg/L and there is a diagnostic dilemma. If sTfR level is raised, a trial of iron therapy is suggested for these patients.