Endocrine Center Research Articles

Spirometry in adult hypothyroid patients: a comparative study.

Hypothyroidism adversely affects pulmonary function, which may improve by thyroxine therapy. Limited studies about the effect of hypothyroidism on spirometric parameters in adult patients were conducted in Basra, south of Iraq. Moreover, the effect of thyroxine therapy on spirometric parameters was not covered by these studies. In this study, pulmonary function in adult's hypothyroid patients was evaluated by spirometry to detect any impairment, type of impairment, and to evaluate the effect of thyroxine therapy. A comparative study was conducted in Al-Faiha Specialized Diabetes, Endocrine, and Metabolism Center (FDEMC) in Al-Faiha teaching hospital, Basrah, Iraq. Subjects are divided into four groups: uncontrolled hypothyroid group (n=72), controlled hypothyroid group (n=60), newly diagnosed hypothyroid group (n=52), and control group (n=110). Spirometry was done to all subjects in sitting position, it's repeated at least three times and the best result was recorded. A significantly (p<0.05) less spirometric parametersand more abnormal pulmonary function test(PFT) were noticed in hypothyroid groups, the reduction were more pronounced in the uncontrolled hypothyroid group. The abnormality in PFT was mostly ofrestrictive type. A significantly (p<0.05) negative correlation hasbeen found between thyroid-stimulating hormone(TSH)and spirometric parameters, while the correlation of fT4is significantly (p<0.05) positive with FVC% and FEV%. In hypothyroidism, high TSH and low fT4 arerecognized causes of a reduction in spirometric parameters. Therefore, spirometry can be used to detect pulmonary function changes in hypothyroidism.

Assessment of knowledge in healthcare workers about diabetes and complication attending structured workshop before Ramadan.

Objectives: Ramadan comes every year, in which Muslims fast for a month according to lunar calendar, which is shorter in duration, and hence can result in Ramadan rotating in different seasons in the same country. Having diabetes, demands a change in life style during fasting, with regular exercise and change in diet patterns. International Diabetes Federation (IDF) has formulated Diabetes and Ramadan (DAR) guidelines, which provide guidance. Assess the knowledge of Healthcare workers before workshop, and to compare afterwards. Study Design: Experimental Study. Setting: Medical Unit-III, Diabetes Endocrine and Metobilc Center Lahore General Hospital, Lahore. Period: 2 years, 2019 and 2020. Material &amp; Methods: This study was carried out on the participants of workshop. A pretest was given to participants. Questions assessed the knowledge on Complications, Risk Stratification, Diet and Exercise, when to break their fast and adjustment in the dosage of different medications used by diabetics. A 90 minute interactive workshop was carried out. Participants were encouraged to question and get justifications for better understanding. Afterwards, a posttest was carried out. Data was assessed using SPSS, and a simple t-test was applied. Results: There was gross improvement in retention of knowledge in all areas. It was also statistically significant when t-test was applied. Conclusion: Interactive workshop pattern improves the retention of knowledge among participants. It was a better way to deliver knowledge, than conventional lecture.

Risk Score of Neck Hematoma: How to Select Patients for Ambulatory Thyroid Surgery?

The risk of postoperative compressive hematoma is the major limitation for a wide development of ambulatory thyroidectomy (AT). The aim of this study was to establish a risk score of hematoma on the basis of preoperative criteria. All patients who underwent thyroidectomy between 2002 and 2017 were reviewed in a high-volume endocrine surgery center. Multivariate analysis of risk factors associated with hematoma was performed in lobectomy and total thyroidectomy (TT). We assigned the risk factors identified by multivariate analysis weighted points proportional to the regression coefficient values. A simple sum of all accumulated points for each patient calculated the total score. For lobectomy [31 hematoma among 3912 patients (0.8%)], the weighted points of Vit K antagonist (VKA) were 3 (OR 9.86), and 1 in male gender (OR 2.4). For TT [162 hematoma among 13,903 patients (1.2%)], the weighted points of VKA were 4 (OR 12.18), 1 in male gender (OR 1.89), and 1 for diabetes (OR 1.86). Other factors weighted 0 in both groups. A total score >1 was linked to a risk of hematoma > 1.3% for lobectomy or TT. AT should not be proposed to any patient under VKA, and in case of TT, to male patients with diabetes. Prospectively, patients had AT from May 2018 to February 2020, 529 patients underwent ambulatory TL (483) or TT (46) and only one patient experienced neck hematoma. We established a simple and reproducible predictive score of early discharge for lobectomy and TT that could be useful for patients' management.

Delineation of the genetic and clinical spectrum, including candidate genes, of monogenic diabetes: a multicenter study in South Korea.

Monogenic diabetes includes a group of heterogeneous diabetes types. We aimed to identify the frequency, clinical and molecular features of monogenic diabetes in a Korean pediatric cohort. A retrospective cohort and multicenter study of Korean children suspected to have monogenic diabetes, managed by four pediatric endocrine centers in the southeast region of South Korea, from February 2016 to February 2020. We recruited 27 pediatric Korean patients suspected to have monogenic diabetes who had at least two of the following three criteria (age at diagnosis, family history, and clinical presentation). Targeted exome sequencing was conducted in these patients. The functional consequences of the variants were predicted by bioinformatics and protein structure analysis. Molecular genetic analysis identified 16 patients (59.3%) with monogenic diabetes. We identified a total ofeight unique variants, including five novel variants (HNF4A c.1088C>T, CEL c.1627C>T and c.1421C>T, PAX4 c.538+8G>C, INS c.71C>T). We also identified two potential candidate gene variants for monogenic diabetes, namely c.650T>C in the SLC2A2 gene and c.629G>A in the PTF1A gene. Other variants were identified in the WFS1and NPHP3 genes in two rare genetic disorders. Variant-positive individuals had a lower presence of autoantibody positivity at the time of diagnosis and higher glycosylated hemoglobin levels at last follow-up when compared to variant-negative patients (p<0.001 and p=0.029, respectively). These results further expand the spectrum of known variants as well as potential candidate gene variants associated with monogenic diabetes in Korea.

Demographic Features and Etiology of Congenital Hypothyroidism at the National Diabetes and Endocrine Center in Oman from 2004 to 2016.

ObjectivesCongenital hypothyroidism (CH) is the most common endocrine disorder in neonates as well as one of the few preventable causes of severe learning difficulties. Early screening, diagnosis, and treatment are mandatory to prevent later sequelae. We sought to determine the demographic and the clinical features of CH in Oman.MethodsWe conducted a retrospective cross-sectional study, including all Omani children newly diagnosed with CH from January 2004 to December 2016 followed at the National Diabetes and Endocrine Center at the Royal Hospital. Those with transient hypothyroidism were excluded from the study. Data collection involved demographic data, clinical manifestations, lab investigations, thyroid scan results, and initiation date of the thyroxine (T4).ResultsA total of 96 patients were newly diagnosed with CH during the study period. Out of the 96 patients, 43 were males (44.8%), and 53 were females (55.2%), and majority were asymptotic (n = 84; 87.5%). Only 78 patients had a thyroid scan. Among those who did the scan, thyroid dysgenesis was the most common (n = 40, 51.3%), followed by dyshormonogenesis (n = 35; 44.9%) and the least was central hypothyroidism (n = 3; 3.8%). The majority of patients (n = 72; 86.7%) were started on T4 therapy within 30 days of life. The remaining (n = 11; 13.3%) had a delay in starting the treatment due to compliance issues, which led to a developmental delay (p < 0.001).ConclusionsThis is the first epidemiological study conducted in Oman that highlights the unique demographic and etiology features of CH. Dyshormonogenesis has a high prevalence in the Omani population compared to other nations. The neurological sequelae in our patients were higher in compression to worldwide prevalence, which was mainly due to delay in starting T4 therapy.

Clinical Presentation, Treatment, and Outcome of Acromegaly in the United Arab Emirates.

ObjectivesWe sought to ascertain the clinical characteristics and control rate of acromegaly in the UAE.MethodsWe conducted a multicenter retrospective analysis of all patients presenting with acromegaly to six endocrine centers in the UAE between November 2010 and December 2018. Demographic, clinical, biochemical, and radiologic data were collected. Patients were considered controlled if normal insulin-like growth factor-1 (IGF-1) level and growth hormone < 1 mcg/L were achieved at their last visit.ResultsA total of 75 patients were included in the study (60.0% males, 33.3% native UAE nationals). The mean age at diagnosis was 37.2 (range: 12–69) years. Common clinical features at diagnosis were headache (82.4%), coarse facial features (82.4%), acral enlargement (79.7%), and sweating (31.3%). Diabetes mellitus/prediabetes and hypertension were present in 45.2% and 35.5% of patients, respectively. About 82.2% had pituitary macroadenoma on pituitary magnetic resonance imaging. At presentation, 27.0% and 3.2% of the patients had secondary hypogonadism and diabetes insipidus, respectively. Overall, 76.7% of the patients underwent surgery, 20.8% received radiotherapy, and 50.7% received medical therapy. At their last clinic visit, only 43.7% of all patients achieved disease control.ConclusionsOur study shows a high prevalence of pituitary macroadenoma in our acromegalic population, suggesting a delayed diagnosis. Also, a significant proportion of patients remained uncontrolled. Efforts to increase physician’s awareness of acromegaly and to improve disease control are underway.

Clinical Characteristics and Long-term Follow-up of Patients with Diabetes Due To PTF1A Enhancer Mutations.

ContextBiallelic mutations in the PTF1A enhancer are the commonest cause of isolated pancreatic agenesis. These patients do not have severe neurological features associated with loss-of-function PTF1A mutations. Their clinical phenotype and disease progression have not been well characterized.ObjectiveTo evaluate phenotype and genotype characteristics and long-term follow-up of patients with PTF1A enhancer mutations.SettingTwelve tertiary pediatric endocrine referral centers.PatientsThirty patients with diabetes caused by PTF1A enhancer mutations. Median follow-up duration was 4 years.Main Outcome MeasuresPresenting and follow-up clinical (birthweight, gestational age, symptoms, auxology) and biochemical (pancreatic endocrine and exocrine functions, liver function, glycated hemoglobin) characteristics, pancreas imaging, and genetic analysis.ResultsFive different homozygous mutations affecting conserved nucleotides in the PTF1A distal enhancer were identified. The commonest was the Chr10:g.23508437A>G mutation (n = 18). Two patients were homozygous for the novel Chr10:g.23508336A>G mutation. Birthweight was often low (median SDS = –3.4). The majority of patients presented with diabetes soon after birth (median age of diagnosis: 5 days). Only 2/30 presented after 6 months of age. All patients had exocrine pancreatic insufficiency. Five had developmental delay (4 mild) on long-term follow-up. Previously undescribed common features in our cohort were transiently elevated ferritin level (n = 12/12 tested), anemia (19/25), and cholestasis (14/24). Postnatal growth was impaired (median height SDS: –2.35, median BMI SDS: –0.52 SDS) with 20/29 (69%) cases having growth retardation.ConclusionWe report the largest series of patients with diabetes caused by PTF1A enhancer mutations. Our results expand the disease phenotype, identifying recurrent extrapancreatic features which likely reflect long-term intestinal malabsorption.

Gender Specific Distribution Of different patterns of Diabetic Retinopathy In Patients With Type 2 Diabetes Mellitus. A Cross-Sectional Study From a tertiary care specialized center in Lahore, Pakistan

BACKGROUND:The patients of diabetic retinopathy are not aware of early retinal vascular dysfunction, which is a feature of diabetic retinopathy.&#x0D; AIM:This study aimed to detect the different patterns of diabetic retinopathy and distribution in different genders, at a tertiary care specialized center.&#x0D; MATERIALS AND METHODS:Consecutive patients attending the Diabetes Endocrine and Metabolic Center (DEMC) were consented and examined for a period of six months. Direct and indirect ophthalmoscopes were used by an ophthalmologist for fundus examination .Grading of the retinopathy patterns was done by International Clinical Diabetic Retinopathy Disease Severity Scale (ICDRDSS). The data was analyzed using SPSS version 23.&#x0D; RESULTS: A total number of 250 patients were examined during the six months period of study. The frequency of diabetic retinopathy was more in females as compared to males. The incidence of non-proliferative diabetic retinopathy was more in males as compared to females, and the prevalence of proliferative diabetic retinopathy was same in both genders. Greater number of females had clinically significant macular edema and advance diabetic retinopathy was observed in only males.&#x0D; CONCLUSION: Diabetic retinopathy (DR) is common in our setup, with different genders having different prevalence of eye problems. A screening strategy system is needed to develop for the early detection and treatment of preventable cause of blindness in patients with type2 diabetes mellitus.

Pure transoral robotic thyroidectomy; institutional adaptation and early results from a tertiary endocrine surgery centre

Novel thyroidectomy techniques have been described to minimize the visible scar. Hereby, we aim to present our experience with transoral robotic thyroidectomy (TORT) without axillary access. Between August 2018 and March 2019, six eligible patients were enrolled to undergo TORT. Procedures were performed by using the Da Vinci Xi platform under intermittent intraoperative nerve monitoring. All patients were female, and the mean age was 40.0 ± 14.4 years. Three patients underwent total thyroidectomy, and lobectomy was performed for the remaining three patients. In one patient, the procedure was converted to conventional open thyroidectomy due to bleeding. The mean docking time, console time and total operative time were 22.8 ± 5.2 min, 118.5 ± 48.7 min and 218.29 ± 50.6 min for total thyroidectomy and 21.8 ± 4.1 min, 68.6 ± 6.1 min and 177.6 ± 15.1 min for lobectomy, respectively. All patients were discharged uneventfully. Pure TORT is a safe procedure, when performed in carefully selected patients by experienced surgeons, but further prospective studies with larger number of patients are required.

Prognostic factor of medullary thyroid carcinoma: Experience of one endocrine center

Prognostic factor of medullary thyroid carcinoma: Experience of one endocrine center

COVID-19 and hypopituitarism. Experience from an endocrine center in a high-impact area

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Clinical profile of patients with solitary thyroid nodules attending tertiary endocrine centre in Kathmandu, Nepal

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Prognostic factors and overall survival in patients with adrenocortical cancer: Experiences of a single tertiary referral endocrine centre in Hungary (1974–2019)

Prognostic factors and overall survival in patients with adrenocortical cancer: Experiences of a single tertiary referral endocrine centre in Hungary (1974–2019)

Clinical profile of thyroid cancer patients attending a tertiary endocrine center in Nepal

Clinical profile of thyroid cancer patients attending a tertiary endocrine center in Nepal

Clinical Routine Application of the Second-generation Neuroendocrine Markers ISL1, INSM1, and Secretagogin in Neuroendocrine Neoplasia: Staining Outcomes and Potential Clues for Determining Tumor Origin

Neuroendocrine neoplasms (NENs) have traditionally been identified via expression of proteins associated to the regulation of secretory vesicles and granules. We report the clinical usage of the “second-generation” proteins ISL LIM homeobox 1 (ISL1), INSM transcriptional repressor 1 (INSM1), and secretagogin (SECG) as immunohistochemical markers of neuroendocrine differentiation since their introduction in clinical routine and compare the results with the established proteins chromogranin A (CGA) and synaptophysin (SYP). In total, 161 tumors, including 139 NENs and 22 “non-NENs” (unrelated tumors with an initial suspicion of NEN), were informatively stained for ISL1, and subsets were also interrogated for INSM1 and/or SECG. Diffuse or focal positive immunoreactivity was noted for ISL1 in 91/139 NENs (65%) and in 6/22 (27%) non-NENs, for INSM1 in 76/85 NENs (89%) and in 2/5 (40%) non-NENs, and for SECG in 49 out of 64 NENs (77%) and in 0/5 non-NENs (0%). Generally, ISL1, INSM1, and SECG exhibited sensitivities in line with or slightly below that of CGA and SYP—largely attributable to tissue-specific patterns regarding tumoral origin. Moreover, for pancreatic and small intestinal NENs, the two largest subgroups, ISL1 staining results were consistent irrespectively of tumor source and WHO grade. We verify previously suggested immunohistochemical schemes of neuroendocrine markers of first- and second-generations to facilitate the diagnostic process for NENs and confirm that the second-generation neuroendocrine markers display tissue-specific patterns. We therefore recommend their implementation in tertiary endocrine pathology centers, not least to aid in the identification of primary tumors when analyzing metastases.

The Clinical Features and Molecular Mechanisms of ACTH-secreting Pancreatic Neuroendocrine Tumors.

Pancreatic neuroendocrine tumors (pNETs) causing ectopic adrenal corticotropic hormone (ACTH) syndrome (EAS) are rare and aggressive with little known information. We aimed to elucidate the clinical features and molecular mechanisms of pNETs with EAS by methylation analysis. Seven patients with ectopic ACTH-secreting pNETs who were diagnosed at Shanghai Clinical Endocrine and Metabolic Diseases Center and Pancreatic Disease Center in Ruijin Hospital between 2001 and 2019 were enrolled. Twenty patients with ectopic ACTH-secreting thymic neuroendocrine tumors (TNETs) and 7 with nonfunctional pNETs (nf-pNETs) were also enrolled as controls. We collected clinical data and measured POMC promoter CpG methylation. All 7 patients had elevated ACTH and urinary free cortisol (UFC) levels with positive ACTH staining in the pancreas and were diagnosed with ectopic ACTH-secreting pNET. Of the 7 patients, 6 underwent surgery and 1 underwent transarterial embolization (TAE). Two patients were free of disease after surgery; 2 died within 90 days after surgery; and 3 had metastases and died within 1 year. Compared with ACTH-secreting TNETs, ACTH-secreting pNETs had similar clinical and biochemical features but a significantly poorer prognosis. POMC promoter CpG methylation was significantly lower in ACTH-secreting pNETs than in nf-pNETs and normal pancreas. ACTH-secreting pNETs are aggressive and fatal. Surgery is definitively curative for patients with resectable primary tumors without metastasis. Pro-opiomelanocortin (POMC) promoter hypomethylation caused pNETs to produce ACTH. This study further supplements the genetic features of ACTH-secreting NETs.

Exendin-4-based imaging in endogenous hyperinsulinemic hypoglycaemia cohort: A tertiary Endocrine centre experience.

Insulinoma needs accurate preoperative localization for minimally invasive surgery. Exendin-4-based imaging has shown promising results. To evaluate performance parameters of exendin-4-based imaging in insulinoma localization and compare with other imaging modalities. Retrospective cross-sectional study. We report 14 patients with endogenous hyperinsulinemic hypoglycaemia (EHH) managed at our centre; in whom, the final diagnosis was insulinoma (n=11), Munchausen syndrome (MS) (n=2) and inconclusive (n=1). Retrospective reporting of CECT, 68 Ga-DOTATATE PET/CT and 68 Ga-NODAGA-exendin-4-PET/CT was done. With per-lesion analysis, performance parameters were calculated for the histopathological diagnosis of insulinoma. True positive (TP), false positive (FP), false negative (FN), true negative (TN), sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) for insulinoma localization. In our cohort, 12 histopathologically proven insulinoma lesions [(TP): 11 primary lesions, 1 metastasis] were detected in 11 patients, whereas two patients had MS (TN). Sn and PPV were 75% and 100%, 33.3% and 80% and 83.3% and 71.4% for CECT, 68 Ga-DOTATATE PET/CT and 68 Ga-NODAGA-exendin-4-PET/CT, respectively. With exendin-4-based imaging, FP uptake in normal pancreatic tissue and FN results in the pancreatic tail lesion was seen. In one patient, TN result suggested the correct diagnosis of MS. 68 Ga-NODAGA-exendin-4-PET/CT has higher sensitivity than 68 Ga-DOTATATE PET/CT and CECT for insulinoma localization. FP uptake in normal pancreas and FN result in tail lesions are limitations of currently utilized exendin-4-based imaging.

Adrenal vein sampling for primary aldosteronism: a 15-year national referral center experience.

BackgroundAdrenal vein sampling (AVS) is essential for diagnostics of primary aldosteronism, distinguishing unilateral from bilateral disease and determining treatment options. We reviewed the performance of AVS for primary aldosteronism at our center during first 15 years, comparing the initial period to the period after the introduction of a dedicated radiologist. Additionally, AVS outcomes were checked against CT findings and the proportion of operated patients with proven unilateral disease was estimated.Patients and methodsA retrospective cross-sectional study conducted at the national endocrine referral center included all patients with primary aldosteronism who underwent AVS after its introduction in 2004 until the end of 2018. AVS was performed sequentially during Synacthen infusion. When the ratio of cortisol concentrations from adrenal vein and inferior vena cava was at least 5, AVS was considered successful.ResultsData from 235 patients were examined (168 men; age 32–73, median 56 years; BMI 18–48, median 30.4 kg/ m2). Average number of annual AVS procedures increased from 7 in the 2004–2011 period to 29 in the 2012–2018 period (p < 0.001). AVS had to be repeated in 10% of procedures; it was successful in 77% of procedures and 86% of patients. The proportion of patients with successful AVS (92% in 2012–2018 vs. 66% in 2004–2011, p < 0.001) and of successful AVS procedures (82% vs. 61%, p < 0.001) was statistically significantly higher in the recent period.ConclusionsNumber of AVS procedures and success rate at our center increased over time. Introduction of a dedicated radiologist and technical advance expanded and improved the AVS practice.

Association of hypovitaminosis D with poor glycemic control and obesity in type II diabetes mellitus.

Objectives: To determine the association of low serum vitamin D levels with poor glycemic control and obesity in type 2 diabetic patients. Study Design: Descriptive Cross Sectional study. Setting: Sakina Institute of Diabetes and Endocrine Research Centre (SIDER), Shalamar Hospital Lahore. Period: 1st June to 31th august 2017. Material &amp; Methods: After applying strict exclusion criteria, about 450 patients with known type II diabetes were enrolled in the present study and their HBA1C and fasting vitamin D levels were measured. Patients were divided into two groups, group 1 with poor glycemic control (HBA1C&gt;8%) and group 2 with good glycemic control (HBA1C &lt;8%). Results: After performing extensive matching in both groups, it was found that vitamin D levels in group 1 with poor glycemic control were significantly low as compared to group 2 with good glycemic control (p value &lt;0.001). Furthermore, approximately 87% of patients with BMI &gt;23 were having suboptimal Vitamin D levels (p value &lt;0.005). Conclusions: Low serum vitamin D is associated with poor glycemic control in type 2 diabetics and vitamin d supplementation could possibly play a role in improving glycemic control in these patients. Furthermore, hypovitaminosis D is also associated with obesity.

The Differential Diagnosis of Discrepant Thyroid Function Tests: Insistent Pitfalls and Updated Flow-Chart Based on a Long-Standing Experience.

Background: Discrepant thyroid function tests (TFTs) are typical of inappropriate secretion of TSH (IST), a rare entity encompassing TSH-secreting adenomas (TSHoma) and Resistance to Thyroid Hormone (RTHβ) due to THRB mutations. The differential diagnosis remains a clinical challenge in most of the cases. The objective of this study was to share our experience with patients presenting with discrepant TFTs outlining the main pitfalls in the differential diagnosis.Methods: medical records of 100 subjects with discrepant TFTs referred to Thyroid Endocrine Centers at the University of Milan were analyzed, retrospectively. Patients were studied by dynamic testing (TRH test, T3-suppression test, or a short course of long-acting somatostatin analog, when appropriate), THRB sequencing, and pituitary imaging.Results: 88 patients were correctly diagnosed as RTHβ with (n = 59; 16 men, 43 women) or without THRB variants (n = 6; 2 men, 4 female) or TSHoma (n = 23; 9 men, 14 women). We identified 14 representative subjects with an atypical presentation or who were misdiagnosed. Seven patients, with spurious hyperthyroxinemia due to assays interference were erroneously classified as RTHβ (n = 4) or TSHoma (n = 3). Three patients with genuine TSHomas were classified as laboratory artifact (n = 2) or RTHβ (n = 1). Two TSHomas presented atypically due to coexistent primary thyroid diseases. In one RTHβ a drug-induced thyroid dysfunction was primarily assumed. These patients experienced a mean diagnostic delay of 26 ± 14 months. Analysis of the investigations which can differentiate between TSHoma and RTHβ showed highest accuracy for the T3-suppression test (100% specificity with a cut-off of TSH <0.11 μUI/ml). Pituitary MRI was negative in 6/26 TSHomas, while 11/45 RTHβ patients had small pituitary lesions, leading to unnecessary surgery in one case.Conclusions: Diagnostic delay and inappropriate treatments still occur in too many cases with discrepant TFTs suggestive of central hyperthyroidism. The insistent pitfalls lead to a significant waste of resources. We propose a revised flow-chart for the differential diagnosis.