The band count imprecision - a Croatian multicentric pilot study.

Introduction: Due to high inter-observer variability the 2015 International Council for Standardization in Haematology (ICSH) recommendations state to count band neutrophils as segmented neutrophils in the white blood cell (WBC) differential. However, the inclusion of bands as a separate cell entity within the WBC differential is still widely used in hematology laboratories in Croatia. The aim of this multicentric study was to assess the degree of inter-observer variability in enumerating band neutrophils within the WBC differential among Croatian laboratories. Materials and methods: Seven large Croatian hospital laboratories from different parts of the country participated in the study. In each of 7 participating laboratories, one blood smear, that was flagged by the analyzer as possibly having bands, was evaluated by all personnel participating in the analysis of hematology samples. Between-observer manual smear reproducibility was expressed as coefficient of variation (CV) and calculated using the following formula: CV (%) = (standard deviation (SD)/mean value) x 100%. Results: The CVs (%) and relative band neutrophil counts in participating laboratories were as follows: 15.4% (16-24), 19.2% (16-32), 19.5% (17-40), 21.1% (17-44), 35.0% (8-26), 51.9% (3-29), and remarkably high 62.4% (12-59). For segmented neutrophils CVs were lower, ranging from 7.4% to 32.2%. The CVs did not correlate with the number of staff members in each hospital (P = 0.293). Conclusions: This study revealed very high variability in enumerating band neutrophil count in the blood smear differential among all participants, thus prompting a need for action on a national level.

Croatian Action on Salt and Health (CRASH): On the Road to Success-Less Salt, More Health.

The World Health Organization recommends adjusting salt intake as a part of the nine global targets to reduce premature mortality from non-communicable chronic diseases as a priority and the most cost-effective intervention. In 2006, the main aim of the Croatian Action on Salt and Health was to decrease salt intake by 16% because of its critical intake and consequences on human health. We have organized educative activities to increase awareness on salt harmfulness, define food categories of prime interest, collaborate with industries and determine salt intake (24 h urine sodium excretion). It was determined that the proportion of salt in ready-to-eat baked bread should not exceed 1.4%. In the period 2014-2022, salt in semi-white bread was reduced by 14%, 22% in bakery and 25% in the largest meat industry. Awareness of the harmfulness of salt on health increased from 65.3% in 2008 to 96.9% in 2023 and salt intake was reduced by 15.9-1.8 g/day (22.8% men, 11.7% women). In the last 18 years, a significant decrease in salt intake was achieved in Croatia, awareness of its harmfulness increased, collaboration with the food industry was established and regulatory documents were launched. However, salt intake is still very high, underlying the need for continuation of efforts and even stronger activities.

Recent data on iodine intake in Croatian schoolchildren: results of 2014-2019 survey.

BACKGROUND: Both insufficient and excessive iodine intake can lead to a broad range of disorders. A cross-sectional survey was conducted to assess iodine status in schoolchildren from Croatia. DESIGN: 957 healthy 6 to 12-year-olds were enrolled (381 from northwestern region, 190 from eastern region, 215 from north Adriatic, and 171 from central Dalmatia region). Urinary iodine concentration (UIC) was measured in spot urine samples. Thyroid volume (Tvol) was recorded by ultrasound device. Standard anthropometric measures were taken, and body surface area (BSA) was determined. Tvol medians were calculated as a function of age, sex and BSA and compared with reference values. RESULTS: Total sample size included 490 boys and 467 girls. Overall median UIC was 250.68 µg/L, with statistically significant variance in geographical regions (median UIC was 244.71 µg/L in northwestern, 208.02 µg/L in eastern, 216.07 µg/L in north Adriatic and 366.43 µg/L in central Dalmatia region). There were 10.08% of samples with UIC < 100 mcg/L while 38.24% of samples had UIC > 300 mcg/L. Age-matched Tvol medians in schoolchildren from all regions of Croatia were at the upper limits of reference values, but in north Adriatic and central Dalmatia exceeded the 97th percentile. BSA-matched Tvol was within the reference range in all regions. CONCLUSIONS: Our results demonstrate sufficient (more than adequate) iodine intake in schoolchildren of Croatia, and excessive iodine intake in central Dalmatia region. Total thyroid volumes in schoolchildren of Croatia were within the normal range, however borderline enlarged age-matched thyroid glands were observed in coastal areas.

THE CONCENTRATION OF INTERLEUKIN 6 AND TUMOR NECROSIS FACTOR ALPHA IN SALIVA AND BLOOD OF PATIENTS WITH INACTIVE MULTIPLE SCLEROSIS AND COEXISTING HASHIMOTO'S THYROIDITIS.

The concentration of interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) in the blood is higher in patients with active multiple sclerosis (MS) compared to those with inactive disease. The concentration of IL-6 and TNF-α in the blood is higher in patients with Hashimoto's thyroiditis (HT) compared to those with a healthy thyroid. The aim of the study was to assess whether serum IL-6 and TNF-α levels correlated with saliva in patients with inactive MS and whether there was a difference in these groups of patients depending of thyroid status. We also examined the correlation of thyroid stimulating hormone (TSH) levels with thyroid status. The study included 54 patients in the inactive phase of MS. The level of cytokines in the blood was determined by chemiluminescence, and in saliva by ELISA. Blood and saliva IL-6 levels showed positive correlation, while blood and saliva TNF-α levels were not correlated. There was a significantly higher TSH level in patients with inactive MS with positive thyroid antibodies, without therapy, compared with those with negative antibodies.

THE PREVALENCE OF SUBCLINICAL HYPOTHYROIDISM IN THE POPULATION OF ELDERLY NURSING HOME RESIDENTS IN ZAGREB.

The aim of the study was to investigate the prevalence of thyroid dysfunction, positive thyroid peroxidase antibodies (TPOAb) and hypercholesterolemia in elderly and younger subjects, and the association of subclinical hypothyroidism with hypercholesterolemia. The study included 204 elderly (136 females and 68 males, age median 71, range 60-92 years), and 83 younger control subjects (63 females and 20 males, age median 45, range 19-55 years). Subjects with prior thyroid dysfunction were excluded. Serum thyrotropin (TSH), free triiodothyronine (FT3), free thyroxine (FT4), TPOAb, total cholesterol, height and weight were measured. Mann-Whitney, χ2-test and Student's t-test were used on statistical analysis. The prevalence of subclinical hypothyroidism (TSH >5 mU/L) in elderly was 7.4% vs. 3.6% in younger subjects, with the highest prevalence of 8.8% in elderly women vs. 4.8% in younger women, and 4.4% in elderly men. The prevalence of hypothyroidism and subclinical hyperthyroidism in elderly subjects was 0.5% and 1.5%, respectively. In women with subclinical hypothyroidism, the prevalence of TPOAb was 77% in elderly women and 67% in younger women (overall 19.9% in elderly and 14.3% in younger women). The mean FT3 level was lower in elderly women as compared with elderly men (p<0.01) and younger women (p<0.05). The mean cholesterol level was higher in elderly subjects in comparison with younger ones (p<0.01), and in elderly women vs. elderly men (p<0.01), but without difference between subclinical hypothyroidism and euthyroid subjects (6.0 mmol/L). In conclusion, subclinical hypothyroidism is the most prevalent thyroid dysfunction in elderly, with the highest prevalence in elderly women, and autoimmune thyroiditis is the most common etiology. Hypercholesterolemia was more related to older age, especially elderly females, but not influenced by subclinical hypothyroidism.

Policies and practices in the field of laboratory hematology in Croatia - a current overview and call for improvement.

OBJECTIVES: In 2019 The Croatian Working Group for Laboratory Hematology, on behalf of the Croatian Society of Medical Biochemistry and Laboratory Medicine, wanted to explore the background in field of laboratory hematology routine practice among Croatian laboratories in order to develop future strategies for producing national recommendations, if needed. METHODS: During April and May 2019, a comprehensive survey covering all main parts of the total testing process within the field of laboratory hematology among Croatian medical laboratories was conducted. The survey comprised 49 inquiries. Data was collected using Survey Monkey (Palo Alto, CA, USA). All collected data was anonymized. RESULTS: The response rate was 72%. There is still a substantial number of laboratories that have only three-part differential hematology analyzers (9%). Furthermore, a very high number of laboratories did not perform analyzer verification prior to implementation into routine work (31%). Out of those who have verified their analyzers, a diversity of guidelines and recommendations were used. Nearly 10% of the laboratories do not have a defined policy regarding specimen rejection. The majority of the participants perform internal quality control daily (83%), however, only 51% of respondents evaluate the agreement between different hematology analyzers on daily basis. Although more than 90% of Croatian laboratories have a defined policy regarding specimen rejection, only 61% of respondents continuously monitor quality indicators in routine practice. CONCLUSIONS: The survey revealed substantial differences in all aspects of laboratory hematology practices among Croatian medical laboratories, indicating the need for universal recommendations at the national level.

IODINE STATUS AND THYROID FUNCTION IN LACTATING WOMEN AND INFANTS - A SURVEY IN THE ZAGREB AREA, CROATIA.

Lactating women (LW) and infants have high dietary iodine requirements and are at risk of iodine deficiency. The aim of the study was to assess iodine status and thyroid function in LW and their breastfed infants in Zagreb, Croatia. The study included 133 LW and breastfed infant pairs. Urinary iodine concentration (UIC) and thyroid function parameters were measured in all subjects. In LW, breast milk iodine concentration (BMIC) was measured and iodine and salt rich food frequency questionnaire data were collected. Results of analysis indicated that 99.2% of the LW used iodized salt in household and 20.4% used iodine-containing vitamin and mineral supplements. Median (IQR) UIC was 75 µg/L (19.0-180.5 µg/L) in LW and 234 µg/L (151.0-367.5 µg/L) in infants, whereas BMIC was 121 µg/kg (87.8-170.8 µg/kg). Multivariate regression analysis revealed BMIC to be a significant predictor of infant UIC (p<0.001). Positive correlation was recorded between LW and infant thyroid function. This was the first study in Croatia demonstrating BMIC to be a reliable biomarker of iodine status during lactation and predicting iodine intake in breastfed infants. The study confirmed that mandatory salt iodization in Croatia ensured sufficient dietary iodine for LW and optimal iodine intake for breastfed infants via breast milk.

THE ROLE OF SALIVARY AND SERUM CA125 AND ROUTINE BLOOD TESTS IN PATIENTS WITH OVARIAN MALIGNANCIES.

The use of routine blood tests has recently been shown to be promising in determining disease-free and overall survival in patients with various malignancies, and also in gynecologic malignancies. The aim of this study was to evaluate whether salivary and serum CA125 levels correlate and whether salivary and serum CA125, C-reactive protein and routine blood tests might serve as a prognostic factor in malignant ovarian tumors, and whether they might differentiate between benign and malignant ovarian tumors. A total of 98 women were included (48 with benign ovarian tumors and 50 with malignant ovarian tumors), in whom routine blood tests were made and salivary and serum CA125 levels were determined by use of ELISA. Increase in serum CA125 and amylase decreased overall survival, whereas increase in salivary CA125, potassium levels and hemoglobin increased overall survival. Significant correlation of serum CA125 and C-reactive protein was found in the group with malignant tumors. In conclusion, significant increase in the levels of serum CA125 and amylase correlated with decreased survival, whereas increased salivary CA125, hemoglobin and potassium levels significantly correlated with increased survival.

Comparison of diagnostic accuracy for eight SARS-CoV-2 serological assays.

INTRODUCTION: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus. MATERIALS AND METHODS: The comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)-negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA). RESULTS: Agreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001). CONCLUSION: There is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.

Women in sports: the applicability of common national reference intervals for inflammatory and coagulation biomarkers (HemSter Study).

INTRODUCTION: Intensive physical activity causes functional and metabolic changes in the athlete's organism. The study aimed to verify the common national available reference intervals (RIs) for common inflammatory and screening coagulation tests in a population of healthy young female athletes. MATERIALS AND METHODS: One hundred and twenty-one female athletes (age range: 16-34), from various sports disciplines (water polo, handball, volleyball, football, basketball), were included in the study. All participants completed the international physical activity short-form questionnaire. Blood samples were collected between 8-10 am, after an overnight fast, before any physical activity. Reference intervals were determined according to Clinical & Laboratory Standards Institute EP28-A3C Guidelines. RESULTS: Calculated RIs for white blood cell count (WBC), prothrombin time (PT), and activated partial thromboplastin time (APTT) ratio were in accordance with the common national RIs. Calculated RI for C-reactive protein (CRP) was lower (< 2.9 mg/L) than the proposed cut-off for a healthy population (< 5.0 mg/L). Reference interval for fibrinogen was higher (1.9-4.4 g/L), than the available RIs (1.8-3.5 g/L). D-dimer cut-off value was set at 852 µg/L fibrinogen equivalent units (FEU), higher than the proposed 500 µg/L FEU for venous thromboembolism (VTE) exclusion. CONCLUSIONS: The applicability of the available RIs for WBC count, PT, and APTT-ratio was confirmed. However, RIs for CRP and fibrinogen differed significantly than the available common national RIs for the healthy non-athletes' population. A higher cut-off for D-dimers should be extensively verified before implementation for VTE diagnosis exclusion in a group of healthy young female athletes.

Salivary Hormones and Quality of Life in Female Postmenopausal Burning Mouth Patients-A Pilot Case-Control Study.

The objective of our study was to investigate salivary levels of estradiol, progesterone and dehydroepiandrosterone (DHEA), and quality of life, in female postmenopausal women with burning mouth syndrome. The study included new patients diagnosed with burning mouth syndrome and excluded local and systemic causes. Unstimulated saliva samples were taken in the morning from 9 AM and 11 AM and immediately frozen for hormone analysis. The patients filled out a self-perceived quality of life questionnaire Oral Health Impact Profile-14 and determined the intensity of mucosal symptoms according to the visual-analog scale grading 0 to 10. A total of 40 patients were included. The study group had significantly lower levels of salivary estradiol. No difference was observed in levels of progesterone and DHEA between the groups. The levels of salivary hormones did not exhibit a significant correlation according to the Spearman correlation test with a self-perceived quality of life questionnaire (OHIP-14) in the study group or in the control group. Further research on a larger number of patients is needed to verify these results. This information might help to enable more precise and efficient treatment.

Salivary Cortisol Levels and Burning Symptoms in Patients with Burning Mouth Syndrome before and after Low Level Laser Therapy: a Double Blind Controlled Randomized Clinical Trial.

OBJECTIVES: Burning mouth syndrome (BMS) is a disorder which is described as burning sensation of the oral mucosa without pathological changes. Most of the patients have some underlying stressful conditions. Stress induces an increase in secretion of different endocrine glands resulting in higher levels of glucocorticoids. One of the options for treatment of BMS includes low level laser therapy (LLLT). The aim of this research was to determine salivary cortisol levels and intensity of burning symptoms in BMS patients before and after LLLT. MATERIALS AND METHODS: Twenty-three participants were allocated by randomization in two groups: 12 patients in the study group and 11 patients in the placebo group. Cortisol levels in all patients were analyzed from the sample of saliva collected without stimulation. In both groups, the LLLT was performed once a day for ten consecutive days (excluding weekend) with Ga-Al-As light-emitting diode type of laser, with a wavelength of 685nm. In the control group, LLLT was done with inactive laser probe which was only emitting audio signal. The intensity of burning symptoms was measured by a visual analogue scale (VAS). The VAS and unstimulated saliva were measured at baseline and on the last day of the LLLT. A quantitative analysis of saliva was performed using competitive commercial ELISA-kit. RESULTS: VAS scores and salivary cortisol levels were significantly lower in both groups after LLLT. CONCLUSIONS: LLLT can be useful in patients with BMS for reducing burning symptoms and salivary cortisol level. Future studies on a larger number of patients should clarify whether the positive results are an outcome of laser effectiveness or of placebo effect.

Women in sports: The applicability of reference intervals for 6 commercially available testosterone immunoassays (HemSter Study).

BACKGROUND: Testosterone levels in female athletes are increased due to their physical activity and correlate with their exercise volume. We therefore hypothesized that the reference intervals (RIs) derived from the general population are not applicable for female athletes. The aim of this study was to evaluate the applicability of the given RIs for 6 commercially available testosterone immunoassays in a group of female athletes. METHODS: Our study included 121 female athletes from various sporting disciplines (water polo, handball, volleyball, football, and basketball). The physical activity score was assessed by the Short Form of the International Physical Activity Questionnaire. Total testosterone was measured in serum samples by the reference LC-MS/MS method and six different immunoassays (Abbott Architect 2nd Generation Testosterone, Beckman Coulter Access Testosterone, Roche Elecsys Testosterone II, Siemens Atellica® IM Testosterone II (TSTII), Siemens IMMULITE 2000 Total Testosterone, and Snibe MAGLUMI™ Testosterone). RESULTS: There were statistically significant differences in age (P = 0.042), weight (P = 0.001), height (P < 0.001), and BMI (P < 0.001) between athletes across different sports. Their quantitative measurements of physical activity and testosterone concentration did not differ significantly between subgroups of various sports, P = 0.167 and P = 0.181, respectively. All immunoassays had a positive absolute and relative bias, in comparison with the LC-MS/MS. The manufacturer's RI was not verified for Abbott Architect, Beckman Coulter Access, and Roche Elecsys Testosterone methods, with the highest percentage of athletes above RI for Beckman Coulter (30%). CONCLUSIONS: We demonstrated that the upper reference limit provided was too low for some young female athletes. Clinical laboratories should consider implementation of the new proposed RIs.

Thyroglobulin Measurement in Needle Aspiration for Detection of Recurrences and Neck Metastases in Patients with Differentiated Thyroid Carcinoma: Significance of Anti-Tg Antibodies.

The worldwide incidence of differentiated thyroid cancer (DTC) has increased in recent decades, likely due to frequent use of cervical ultrasonography (US) and US-guided fine needle aspiration biopsy (FNA)., US is performed during follow-up after thyroidectomy, and US-guided FNA with cytology is used if suspicious cervical lymph nodes (LN) or thyroid bed masses are detected. Knowing that serum anti-Tg antibodies (sTgAb) affect the use of serum Tg (sTg) as a tumor marker, the aim of our study was to assess the usefulness of Tg determination in needle aspirates (FNA-Tg) in presence of sTgAb. This retrospective study included 149 patients with DTC and 159 aspirations of suspicious LN and thyroid bed masses. As expected, there was a negative correlation between sTg and sTgAb levels (p<0.05), while FNA-Tg levels had a positive correlation with FNA-TgAb levels (p<0.05). Furthermore, we found a positive correlation between sTg and FNA-Tg levels (p<0.05), but not between sTgAb and FNA-TgAb or sTgAb and FNA-Tg. In conclusion, these results show that FNA-Tg values were not affected by sTgAb and that FNA-Tg measurement were highly effective in detecting cervical DTC metastases. However, combined use with cytology is suggested for neck evaluation because cytology could reveal metastases from other tumor sites.

Knowledge and awareness of iodine intake - survey among Croatian women of reproductive age.

INTRODUCTION: Appropriate iodine intake is important for the entire population, especially in fertile women due to decisive role of thyroid hormones in normal foetal brain development. The aim of this study was to investigate knowledge on iodine role among Croatian women of reproductive age. MATERIALS AND METHODS: The survey was conducted among 378 women of reproductive age during May-September 2018. Data on age, education level, salt intake habits, knowledge of the iodine role and possible presence of thyroid disease were collected and results were presented as numbers or percentage of total number of participants. Comparison between groups was performed by Chi square test. RESULTS: Of 378 participants, 178 reported to be familiar with the iodine role in the body (P = 0.115). Significantly higher proportion of the younger woman and woman with lower degree of education weren't familiar with the iodine role (P < 0.001). More woman were introduced to consequences of insufficient than to excessive iodine intake (273 vs 213; P < 0.001). In addition, participants mainly weren't familiar with obligation of salt iodination (P < 0.001). Presence of thyroid disease was recorded in 75 subjects with higher prevalence in subjects 36-49 years (P < 0.001). Presence of thyroid disease was not associated with knowledge on iodine role on health. CONCLUSION: Women of reproductive age are not completely aware of the consequences of excessive iodine intake. Thus, further education focusing on more sensitive groups such as woman of younger age should be considered in order to preserve their and their children's health.

Corrigendum to: Analytical evaluation of the new Seal Autoanalyzer 3 High Resolution for urinary iodine determination.

[This corrects the article DOI: 10.11613/BM.2019.020711.].

Analytical evaluation of the new Seal Autoanalyzer 3 High Resolution for urinary iodine determination.

INTRODUCTION: The aim of the study was to evaluate the analytical performance of the new colorimetric, automatic analyser, Seal AutoAnalyzer 3 High Resolution (Seal AA3 HR) (Seal Analytical, Wisconsin, USA) for urinary iodine measurement. MATERIALS AND METHODS: This study included testing of several analytical features of the method involving: imprecision (within-run %CVr, between-run %CVb and total laboratory precision %CVl), measurement uncertainty, carryover, linearity and method comparison, with 70 urine samples including the measuring range (20 - 700 µg/L). RESULTS: Within-run, %CVb and %CVl of two control levels were 2.03% and 3.04%, 0.51% and 2.61%, and 2.09% and 4.01%, respectively. Carryover effect was less than 1%. The linearity was good in the range of urinary iodine values between 60 and 500 µg/L (R2 = 0.99). Good agreement of urinary iodine values was found between manual technique and Seal AA3 HR, using Passing-Bablok regression (y = 7.84 (- 3.00 to 15.29) + 0.95 (0.90 to 1.00) x) and Blant-Altman test. Cusum test for linearity indicates that there is no significant deviation from linearity (P > 0.1). CONCLUSIONS: The obtained results proved excellent precision, reproducibility and linearity, comparable to the already used, manual method. The New Seal AA3 HR automatic analyser is acceptable for urinary iodine measurement with very good analytical characteristics and can be used for urinary iodine epidemiological studies of the Croatian population.

Salivary Cortisol Levels in Patients with Oral Lichen Planus-A Pilot Case-Control Study.

It is known that cortisol level increases in stress situations. The aim of the study was to measure the levels of salivary cortisol in patients with oral lichen planus (OLP) and healthy controls. This was a case-control pilot study which included seven patients with reticular (non-symptomatic) OLP, eight patients with atrophic/erosive (symptomatic) OLP, and nine healthy controls. We hypothesized that patients with an atrophic/erosive type of OLP have higher levels of cortisol compared to patients with the reticular type of OLP and healthy controls. In each participant, unstimulated saliva was collected in order to determine cortisol levels by using commercially available ELISA kit. Our results have shown no differences between levels of salivary cortisol in OLP patients and healthy controls. We can conclude that further research with a larger number of OLP patients is needed to determine the correlation between OLP and stress.

The quality and scope of information provided by medical laboratories to patients before laboratory testing: Survey of the Working Group for Patient Preparation of the Croatian Society of Medical Biochemistry and Laboratory Medicine.

INTRODUCTION: The aim of this work was to evaluate to what extent the scope and content of information provided to patients is standardized across medical biochemistry laboratories in Croatia. MATERIALS AND METHODS: Two on-line self-report surveys were sent out: Survey A regarding attitudes on importance of patient preparation and Survey B on the contents of patient preparation instructions. RESULTS: 13/118 laboratories (11%) do not provide written instructions to patients on how to prepare for laboratory testing, and 36 (40%) do not include information about water intake in their instructions. Only half of laboratories provide instructions for prostate-specific antigen (53.8%), female sex hormones (53.7%) and therapeutic drug monitoring (TDM) (52.5%). Inadequate information about fasting status (55.0%) and 24 hour urine collection (77.9%) were frequent errors with high severity and were associated with the greatest potential to cause patient harm. CONCLUSIONS: Laboratory professionals in Croatia have a positive attitude towards the importance of patient preparation for laboratory testing. However, the information for laboratory testing is not standardized and frequently lacks guidance for tests related to TDM, coagulation and endocrinology. This study highlights the need for standardized, updated and evidence-based recommendations for patient preparation in order to minimize the risk for patients.

Platelet satellitism in infectious disease?

BACKGROUND: Platelet satellitism is a phenomenon of unknown etiology of aggregating platelets around polymorphonuclear neutrophils and other blood cells which causes pseudothrombocytopenia, visible by microscopic examination of blood smears. It has been observed so far in about a hundred cases in the world. CASE SUBJECT AND METHODS: Our case involves a 73-year-old female patient with a urinary infection. Biochemical serum analysis (CRP, glucose, AST, ALT, ALP, GGT, bilirubin, sodium, potassium, chloride, urea, creatinine) and blood cell count were performed with standard methods on autoanalyzers. Serum protein fractions were examined by electrophoresis and urinalysis with standard methods on autoanalyzer together with microscopic examination of urine sediment. Erythrocyte sedimentation rate, blood culture and urine culture tests were performed with standard methods. RESULTS: Due to typical pathological values for bacterial urinary infection, the patient was admitted to the hospital. Blood smear examination revealed phenomenon, which has persisted for three weeks after the disease has been cured. Blood smears with EDTA as an anticoagulant had platelet satellitism whereas the phenomenon was not observed in tubes with different anticoagulants (Na, Li-heparin) and capillary blood. DISCUSSION: We hypothesize that satellitism was induced by some immunological mechanism through formation of antibodies which have mediated platelets binding to neutrophil membranes and vice versa. Unfortunately we were unable to determine the putative trigger for this phenomenon. To our knowledge this is the second case of platelet satellitism ever described in Croatia.