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Objective: Maturity onset diabetes of the young (MODY) occurs due to mutations in genes involved in pancreatic beta cell function and insulin secretion, has heterogeneous clinical and laboratory features, and account for 1-5% of all diabetes cases. The prevalence and distribution of MODY subtypes vary between countries. The aim of this study was to evaluate the clinical and laboratory characteristics, mutation distribution, and phenotype-genotype relationship in a large case series of pediatric Turkish patients genetically diagnosed with MODY. Methods: MODY cases from 14 different pediatric endocrinology departments were included. Diagnosis, treatment, follow-up data, and results of genetic analysis were evaluated. Results: A total of 224 patients were included, of whom 101 (45%) were female, and the mean age at diagnosis was 9.4±4.1 years. Gene variant distribution was: 146 (65%) GCK; 43 (19%) HNF1A; 8 (3.6%) HNF4A, 8 (3.6%) KLF11 and 7 (3.1%) HNF1B. The remaining 12 variants were: PDX (n=1), NEUROD1 (n=3), CEL (n=1), INS (n=3), ABCC8 (n= 3) and KJNC11 (n=1). Of the cases, 197 (87.9%) were diagnosed with incidental hyperglycemia, 16 with ketosis (7%) and 7 (3%) with diabetic ketoacidosis (DKA), while 30% presented with classical symptoms of diabetes. Two-hundred (89%) had a family history of diabetes. Anti-GAD antibody was detected in 13 cases, anti-islet antibody in eight and anti-insulin antibody in four. Obesity was present in 16. Distribution of therapy was: 158 (71%) diet only; 23 (11%) intensive insulin treatment; 17 (7.6%) sulfonylureas; 10 (4.5%) metformin; and 6 (2.7%) insulin and oral anti-diabetic treatment. Conclusion: This was the largest genetically diagnosed series from Turkey. The most common gene variants were GCK and HNF1A with much lower proportions for other MODY types. Hyperglycemia was the most common presenting symptom while 11% of patients had diabetes-associated autoantibodies and 7% were obese. The majority of patients received dietary management only. [ABSTRACT FROM AUTHOR]

We investigated depression and anxiety levels and related psychological disorders in adolescents with transfusion-dependent thalassemia (TDT) in this study. The study was conducted in two pediatric hematology outpatient clinics and included adolescents with TDT (14.8 ± 2.4 years, n = 40) in the study and compared them with the healthy age-matched control group (14.3 ± 2.3 years, n = 62). The Turkish version of the Revised Child Anxiety and Depression Scale (RCADS) was used to determine depression, anxiety, and related psychologic disorders (obsession, panic disorder, social phobia). Depression, anxiety, obsession, panic disorder, and social phobia scores were significantly higher in the patient group compared with the control (all p < 0.05). Ferritin levels were positively correlated with total depression, general anxiety, separation anxiety, and social phobia scores, but transfusion frequency and young age were the confounding factors. Patients in early adolescence and those who require more frequent blood transfusions are at higher risk of developing psychological disorders; routine screening for mood disorders should be warranted. Serum ferritin level may be a good warning indicator for early recognition of psychologic disorders in TDT patients. [ABSTRACT FROM AUTHOR]

Objective: Recent reports have indicated the role of the prokineticin receptor 2 gene (PROKR2) in the etiology of pituitary hormone deficiencies, suggesting a potential role for the PROK2 pathway in pituitary development, in addition to its role in gonadotropin releasing hormone-expressing neuron development. Here, we present the clinical and molecular findings of four patients with PROKR2 mutations. Methods: Next-generation targeted sequencing was used to screen 25 genes in 59 unrelated patients with multiple pituitary hormone deficiency (MPHD), isolated growth hormone (GH) deficiency, or idiopathic short stature. Results: Two different, very rare PROKR2 missense alterations classified as pathogenic (NM_144773.4:c.518T>G; NP_658986.1:p. (Leu173Arg)) and likely pathogenic (NM_144773.4:c.254G>A; NP_658986.1:p.(Arg85His)) were identified in four patients in heterozygous form. Patient 1 and Patient 2 presented with short stature and were diagnosed as GH deficiency. Patient 3 and Patient 4 presented with central hypothyroidism and cryptorchidism and were diagnosed as MPHD. No other pathogenic alterations were detected in the remaining 24 genes related to short stature, MPHD, and hypogonadotropic hypogonadism. Segregation analysis revealed asymptomatic or mildly affected carriers in the families. Conclusion: PROKR2 dominance should be kept in mind as a very rare cause of GH deficiency and MPHD. Expressional variation or lack of penetrance may imply oligogenic inheritance or other environmental modifiers in individuals who are heterozygous carriers. [ABSTRACT FROM AUTHOR]

Objective: A significant rise in the number of trans adolescents seeking medical interventions has been reported in recent years. The aim of this study was to report the clinical features, treatment, and follow-up of adolescents with gender dysphoria (GD) with our increased experience. Methods: Twenty-six male-to-female (MTF) and twenty-seven female-to-male (FTM) adolescents who were referred to the GD-outpatient clinic between 2016 and 2022 were reviewed. The clinical and laboratory findings of thirty transgender adolescents (15 FTM/15 MTF) who received medical intervention were evaluated retrospectively. Results: Most individuals (60.4%) were admitted between 2020 and 2022, and the remaining (39.6%) were admitted between 2016 and 2019. At the time of referral, median age was 16.3 years [interquartile range (IQR) 1.53; range 13.2-19.4] in 26 MTF, and 16.4 years (IQR 1.74; range 11.7-21.6) in 27 FTM adolescents. The median age at pubertal blockage with gonadotropin-releasing hormone analog and androgen receptor blocker was 16.4 years (IQR 1.4; range 11.7-17.8) in 22 adolescents (9 MTF, 13 FTM), and 17.4 years (IQR 1.4; range 15.5-19.4) in 6 MTF individuals, respectively. Cross-sex hormone therapy was commenced in 21 adolescents (12 MTF, 9 FTM) at the median age of 17.7 years (IQR 0.61; range 16-19.5). Fifteen individuals (8 MTF, 7 FTM) have been transferred to the adult endocrinology department in transition clinics. Conclusion: All treatments were generally well tolerated and effective, including bicalutamide, and no significant side effects were observed. Transition clinics played an important role in the better management of gender reassignment processes. [ABSTRACT FROM AUTHOR]

Objective: Brain tumors in childhood carry a high risk for endocrine disorders due to the direct effects of the tumor and/or surgery and radiotherapy. Somatotropes are vulnerable to pressure and radiotherapy; therefore, growth hormone deficiency is one of the most frequent abnormalities. This study aimed to evaluate endocrine disorders and recombinant growth hormone treatment outcomes in brain tumor survivors. Materials and Methods: In this study, 65 (27 female) patients were classified into 3 groups as craniopharyngioma (n = 29), medulloblastoma (n = 17), and others (n = 19). “Others” group included astrocytoma, ependymoma, germinoma, pineoblastoma, and meningioma patients. Anthropometric data and endocrine parameters of patients and their growth outcome with/without recombinant growth hormone therapy were collected from medical records, retrospectively. Results: Mean age at the first endocrinological evaluation was 8.7 ± 3.6 years (range: 1.0- 17.1 years). Height, weight, and body mass index standard deviation score, mean ± standard deviation (median) values were −1.7 ± 1.7 (−1.5), −0.8 ± 1.9 (−0.8), and 0.2 ± 1.5 (0.4), respectively. Hypothyroidism (central 86.9%, primary 13.1%) was detected during follow-up in 81.5% of patients. Primary hypothyroidism in medulloblastoma (29.4%) was significantly higher compared to other groups (P = .002). The frequency of hypogonadotropic hypogonadism, central adrenal insufficiency, and diabetes insipidus was significantly high in the craniopharyngioma cases. Conclusion: In our study, endocrine disorders other than growth hormone deficiency were also frequently observed. In craniopharyngioma cases, the response to recombinant growth hormone therapy was satisfactory. However, there was no improvement in height prognosis during recombinant growth hormone therapy in medulloblastoma patients. A multidisciplinary approach to the care of these patients, referral for endocrine complications, and guidelines on when recombinant growth hormone therapy is required. [ABSTRACT FROM AUTHOR]

Objective: Using World Health Organization (WHO) standards in pediatric practice is still controversial in many countries. It is suggested that national growth charts best reflect the genetic and ethnic characteristics of a population. The aim of this study was to compare length/height, body weight, and body mass index (BMI) in healthy Turkish children of ages 0 to 18 with those proposed by WHO as the international growth standards. Methods: The data of Turkish children were collected from infant/child population aged 0-5 years (2391 boys, 2102 girls) and children of ages between 6-18 years (1100 boys, 1020 girls). For comparison, the 50th, 3rd, and 97th percentile curves for length/height, weight, and BMI in Turkish children were plotted together with respective WHO data. Results: Heights were essentially similar in the Turkish and WHO data at ages between 3-10 years. Turkish children were markedly taller compared to the WHO standards after the age of 10 years. Evaluation of the 3rd percentile data revealed that Turkish boys were shorter than the WHO subjects in the first 2 years of life. From 6 months of age, Turkish children showed higher weight for age values in the 3rd, 50th, and 97th percentiles. In all age groups between 6 months and 3 years, and in between 6-18 years of age, Z-score values, as well as the 50th, 15th, 85th, and 95th percentile values were higher in Turkish children. The differences were particularly noteworthy at ages 1-2 years and in the pubertal years. Conclusion: WHO growth standards do not reflect the growth of Turkish children and may substantially alter the prevalence of short stature and underweight in Turkish children in the 0-5 years age group. When assessing the nutritional and growth status of children, national growth standards may be more appropriate. [ABSTRACT FROM AUTHOR]

Objective: Androgen insensivity syndrome (AIS) and 5α-reductase deficiency (5α-RD) present with indistinguishable phenotypes among the 46,XY disorders of sexual development (DSD) that usually necessitate molecular analyses for the definitive diagnosis in the prepubertal period. The aim was to evaluate the clinical, hormonal and genetic findings of 46,XY DSD patients who were diagnosed as AIS or 5α-RD. Methods: Patients diagnosed as AIS or 5α-RD according to clinical and hormonal evaluations were investigated. Sequence variants of steroid 5-α-reductase type 2 were analyzed in cases with testosterone/dihydrotestosterone (T/DHT) ratio of ≥20, whereas the androgen receptor (AR) gene was screened when the ratio was <20. Stepwise analysis of other associated genes were screened in cases with no causative variant found in initial analysis. For statistical comparisons, the group was divided into three main groups and subgroups according to their genetic diagnosis and T/DHT ratios. Results: A total of 128 DSD patients from 125 non-related families were enrolled. Birth weight SDS and gestational weeks were significantly higher in 5α-RD group than in AIS and undiagnosed groups. Completely female phenotype was higher in all subgroups of both AIS and 5α-RD patients than in the undiagnosed subgroups. In those patients with stimulated T/DHT <20 in the prepubertal period, stimulated T/DHT ratio was significantly lower in AIS than in the undiagnosed group, and higher in 5α-RD. Phenotype associated variants were detected in 24% (n=18 AIS, n=14 5α-RD) of the patients, revealing four novel AR variants (c.94G>T, p.Glu32*, c.330G>C, p.Leu110=; c.2084C>T, p.Pro695Leu, c.2585_2592delAGCTCCTG, p.(Lys862Argfs*16), of these c.330G>C with silent status remained undefined in terms of its causative effects. Conclusion: T/DHT ratio is an important hormonal criterion, but in some cases, T/DHT ratio may lead to diagnostic confusion. Molecular diagnosis is important for the robust diagnosis of 46,XY DSD patients. Four novel AR variants were identified in our study. [ABSTRACT FROM AUTHOR]

Objective: To investigate clinical characteristics and response to growth hormone (GH) treatment in patients with Prader-Willi syndrome (PWS) in Turkey. Methods: The data of 52 PWS patients from ten centers was retrospectively analyzed. A nation-wide, web-based data system was used for data collection. Demographic, clinical, genetic, and laboratory data and follow-up information of the patients were evaluated. Results: The median age of patients at presentation was 1.5 years, and 50% were females. Genetic analysis showed microdeletion in 69.2%, uniparental disomy in 11.5%, imprinting defect in 1.9% and methylation abnormality in 17.3%. Hypotonia (55.7%), feeding difficulties (36.5%) and obesity (30.7%) were the most common complaints. Cryptorchidism and micropenis were present in 69.2% and 15.3% of males, respectively. At presentation, 25% had short stature, 44.2% were obese, 9.6% were overweight and 17.3% were underweight. Median age of obese patients was significantly higher than underweight patients. Central hypothyroidism and adrenal insufficiency were present in 30.7% and 4.7%, respectively. Hypogonadism was present in 75% at normal age of puberty. GH treatment was started in 40% at a mean age of 4.7±2.7 years. After two years of GH treatment, a significant increase in height SDS was observed. However, body mass index (BMI) standard deviation (SDS) remained unchanged. Conclusion: The most frequent complaints were hypotonia and feeding difficulty at first presentation. Obesity was the initial finding in 44.2%. GH treatment was started in less than half of the patients. While GH treatment significantly increased height SDS, BMI SDS remained unchanged, possibly due to the relatively older age at GH start. [ABSTRACT FROM AUTHOR]

Objective: To retrospectively evaluate the follow-up data in patients with 46,XX congenital adrenal hyperplasia (CAH) who were raised male. Methods: A national database was created. The data of patients were asked to be recorded in the data form. Results: The median (range) age of diagnosis was three (0.1-18.3) years in 44 patients. Twenty nine cases were diagnosed after the age of two years. Most (95.4%) cases were stage 4-5 virilized. Hysterectomy and bilateral salpingoopherectomy, at a median age of 7.25 (2.4-25.3) years, was performed in 35 cases. Testicular prostheses were placed in 11 (25%) cases at a median age of 11.2 (2.8-17) years. The median final height was 149.2 (132.8-172) cms in 38 patients, including simple virilizing (n=18), salt-wasting (n=6), and 11-beta hydroxylase (n=12). Of the 16 patients above the age of eighteen, university education was completed in 25%. Conclusion: It was seen that most (65.9%) of the 46,XX CAH cases raised male were diagnosed after two years of age. In these cases, hysterectomy and bilateral salpingoopherectomy, genital corrective surgeries and testicular prosthesis operations were performed in a very wide age rage. [ABSTRACT FROM AUTHOR]

Acid-labile subunit (ALS) forms ternary complexes with insulin like growth factor-1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) and is essential for normal circulating IGF-1 levels. The IGFALS gene encodes the ALS and mutations in IGFALS cause ALS deficiency. We describe a patient with ALS deficiency with a novel homozygous frameshift mutation in IGFALS presenting with short stature and delayed puberty but ultimately achieving an adult height (AH) comparable to his target height (TH). A 15.25 year old boy presented with short stature (149.9 cm, -3.04 standard deviation score). The patient had a low circulating IGF-1 concentration, extremely low IGFBP-3 concentration, insulin resistance and osteopenia. The peak growth hormone (GH) response to GH stimulation test was high (31.6 ng/ mL). Sequencing of IGFALS revealed a novel, homozygous, frameshift mutation (p.Ser555Thrfs.19). His mother and elder sister were heterozygous carriers. Although he had delayed puberty and short stature at the onset of puberty, he reached his TH and an AH similar to those of his heterozygous mother and sister. The heterozygous carriers had normal or low IGF-1 concentrations and low IGFBP-3 concentrations but not as markedly low as that of the patient. They had normally timed puberty, insulin metabolism and bone mineral density (BMD). The phenotype of ALS deficiency is quite variable. Despite short stature and delayed puberty, patients can achieve normal pubertal growth and AH. ALS deficiency may cause osteopenia and hyperinsulinemia. Heterozygous carriers may have normal prenatal growth, puberty, insulin metabolism and BMD. [ABSTRACT FROM AUTHOR]

Objective: We aimed to report the characteristics at admission, diagnosis, treatment, and follow-up of cases of pediatric hyperprolactinemia in a large multicenter study. Methods: We reviewed the records of 233 hyperprolactinemic patients, under 18 years of age, who were followed by different centers. The patients were divided as having microadenomas, macroadenomas, drug-induced hyperprolactinemia and idiopathic hyperprolactinemia. Complaints of the patients, their mode of treatment (medication and/or surgery) and outcomes were evaluated in detail. Results: The mean age of the patients with hyperprolactinemia was 14.5 years, and 88.4% were females. In terms of etiology, microadenomas were observed in 32.6%, macroadenomas in 27%, idiopathic hyperprolactinemia in 22.7% and drug-induced hyperprolactinemia in 6.4%. Other causes of hyperprolactinemia were defined in 11.3%. Common complaints in females (n=206) were sorted into menstrual irregularities, headaches, galactorrhea, primary or secondary amenorrhea and weight gain, whereas headache, gynecomastia, short stature and blurred vision were common in males (n=27). Median prolactin levels were 93.15 ng/mL, 241.8 ng/mL, 74.5 ng/mL, 93.2 ng/mL, and 69 ng/mL for microadenomas, macroadenomas, idiopathic hyperprolactinemia, drug-induced hyperprolactinemia, and other causes of hyperprolactinemia, respectively. Of 172 patients with hyperprolactinemia, 77.3% were treated with cabergoline and 13.4% with bromocriptine. 20.1% of the patients with pituitary adenomas underwent pituitary surgery. Conclusion: We present the largest cohort of children and adolescents with hyperprolactinemia in the literature to date. Hyperprolactinemia is more common in females and cabergoline is highly effective and practical to use in adolescents, due to its biweekly dosing. Indications for surgery in pediatric cases need to be revised. [ABSTRACT FROM AUTHOR]

Objective: 17α-hydroxylase/17,20 lyase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia (CAH), characterized by hypertension and varying degrees of ambiguous genitalia and delayed puberty. The disease is associated with bi-allelic mutations in the CYP17A1 gene located on chromosome 10q24.3. We aimed to present clinical and genetic findings and follow-up and treatment outcomes of 17OHD patients. Methods: We evaluated six patients with 17OHD from five families at presentation and at follow up. Standard deviation score of all auxological measurements was calculated according to national data and karyotype status. CYP17A1 gene sequence alterations were investigated in all patients. Results: The mean (±standard deviation) age of patients at presentation and follow-up time was 14.6±4.2 and 5.0±2.7 years respectively. Five patients were referred to us because of delayed puberty and primary amenorrhea and four for hypertension. One novel single nucleotide insertion leading to frame shift and another novel variant occurring at an ultra rare position, leading to a missense change, are reported, both of which caused 17OHD deficiency. Steroid replacement was started. The three patients with 46,XY karyotype who were raised as females underwent gonadectomy. Osteoporosis was detected in five patients. Four patients needed antihypertensive treatment. Improvement in osteoporosis was noted with gonadal steroid replacement and supportive therapy. Conclusion: 17OHD, a rare cause of CAH, should be kept in mind in patients with pubertal delay and/or hypertension. Patients with 46,XY who are raised as females require gonadectomy. Due to late diagnosis, psychological problems, gender selection, hypertension and osteoporosis are important health problems affecting a high proportion of these patients. [ABSTRACT FROM AUTHOR]

Objective: Papillary thyroid cancer (PTC) may behave differently in prepubertal children as compared to pubertal children and adults. BRAF gene activating mutations may associate with PTC by creating aberrant activation. We aimed to evaluate the clinicopathological characteristics of PTC patients with emphasis on the pubertal status and also to investigate the association of BRAFV600E mutation with disease characteristics. Methods: The medical records of 75 patients with PTC were reviewed retrospectively. BRAFV600E mutation status was available only in the medical records of 56 patients. Results: Mean age at diagnosis was 12.4±3.8 years. There was no difference in sex, initial signs, tumor histopathology, and pathological evidence of tumor aggressiveness between prepubertal and pubertal children. Although not statistically significant, lateral neck nodal metastasis and lung metastasis at diagnosis were more prevalent in prepubertal children. After excluding patients with microcarcinoma, prepubertal children were found to require lateral neck dissection and further doses of radioactive iodine more frequently than pubertal patients. Recurrence was also more frequent in prepubertal children (p=0.016). Frequency of BRAFV600E mutation was similar in prepubertal and pubertal patients. BRAFV600E mutation was found in 14/56 (25%) patients and was high in the classic variant PTC (p=0.004). Multicentricity was high in BRAFV600E mutation (p=0.01). There was no relation between BRAFV600E mutation and lymph node and pulmonary metastasis at diagnosis, or between BRAFV600E mutation and pathological evidence of tumor aggressiveness. Conclusion: PTC is more disseminated in prepubertal children. BRAFV600E mutation does not correlate with a more extensive or aggressive disease. BRAFV600E mutation is not the cause of the differences in the biological behavior of PTC in prepubertal and pubertal children. [ABSTRACT FROM AUTHOR]

Objective: Polycystic ovary syndrome (PCOS) is a common endocrine problem in adolescents with an increasing prevalence of 30%. Pursuing new biomarkers with high specificity and sensitivity in the diagnosis of PCOS in adolescents is currently an active area of research. We aimed to investigate the diagnostic value of anti-Müllerian hormone (AMH), insulin-like peptide-3 (INSL3), inhibin-A (INH-A), and inhibin-B (INH-B) in adolescents with PCOS and also to determine the association, if any, between these hormones and clinical/laboratory findings related with hyperandrogenism. Methods: The study group comprised 53 adolescent girls aged between 14.5 and 20 years who were admitted to our outpatient clinic with symptoms of hirsutism and/or irregular menses and diagnosed as having PCOS in accordance with the Rotterdam criteria. Twenty-six healthy peers, eumenorrheic for at least two years and body mass index-matched, constituted the controls. Fasting blood samples for hormones [luteinizing hormone (LH), follicle-stimulating hormone (FSH), dehydroepiandrosterone-sulfate (DHEAS), androstenedione (D4-A), total/free testosterone (T/fT), sex hormone binding globulin (SHBG), AMH, INSL3, INH-A, INH-B] were drawn after an overnight fast. Results: In the PCOS group, 83% of the subjects were oligomenorrheic/ amenorrheic and 87% had hirsutism. The LH, LH/FSH ratio, total T, fT, free androgen-index (FAI), DHEAS levels were significantly higher (p=0.005, p=0.042, p=0.047, p<0.001, p=0.007, p=0.014, respectively) and SHBG was significantly lower (p=0.004) in PCOS patients as compared to the controls. Although the INSL-3 and INH-B levels showed no difference between the groups (p>0.05), AMH and INH-A levels were found to be significantly higher in the PCOS group compared to the controls (p<0.001, p<0.001, respectively). In multiple linear regression analysis, WC SDS (p=0.028), logD4-A (p=0.033), logSHBG (p=0.031), and total ovarian volume (p=0.045) had significant effects on AMH levels, and LH (p=0.003) on INH-A levels. In receiver-operating characteristic analysis, the cut-off values for AMH and INH-A were 6.1 ng/mL (sensitivity 81.1%) and 12.8 pg/mL (sensitivity 86.8%), respectively, to diagnose PCOS. When AMH and INH-A were used in combination, the sensitivity (96.2%) increased. Conclusion: INSL3 and INH-B were not found to have diagnostic value in adolescents with PCOS. On the other hand, it was shown that INH-A could be used as a new diagnostic biomarker in addition to AMH. [ABSTRACT FROM AUTHOR]

Background Although studied widely in adulthood, little is known about endocrinological disorders during critical illnesses in childhood. The aims of this study were to define the endocrinological changes in patients admitted to pediatric intensive care unit ( PICU) and to identify their effects on prognosis. Methods Forty patients with a mean age of 5.1 years admitted to PICU were enrolled in the study. Blood samples were taken at admission and at 24 and 48 h to measure cortisol, adrenocorticotropic hormone ( ACTH), prolactin, growth hormone ( GH), GH binding protein ( GHBP), insulin-like growth factor-binding protein-3 ( IGFBP-3) and interleukin-6 ( IL-6). The severity of the patient's condition was assessed using pediatric risk of mortality ( PRISM) and pediatric logistic organ dysfunction ( PELOD) scores. Results PRISM and PELOD scores were significantly higher in non-survivors. Cortisol, ACTH, prolactin, GH, GHBP, IGFBP-3 and IL-6 were not significantly different between the survivors and non-survivors. There was a negative correlation between baseline IGFBP-3 and PRISM scores. A positive correlation was seen between cortisol level at 24 h and PRISM score. On multivariate linear regression analysis, PRISM score was best explained by ACTH and cortisol at 24 h. A positive weak correlation was detected between IL-6 at 24 h and PELOD scores. Conclusions Although there was no difference between survivors and non-survivors regarding the studied endocrine parameters, there were associations between cortisol, ACTH, IL-6 and IGFBP-3 and risk assessment scores, and, given that these scores correlated with mortality, these parameters might be useful as prognostic factors. [ABSTRACT FROM AUTHOR]