Failure rate prediction of equipment: can Weibull distribution be applied to automated hematology analyzers?

Background Life cycle prediction measures, that provide information on the probability of failure of equipments, have been applied in electronic and mechanical engineering and for predicting the strength of dental implants. However, the same has not been utilized as yet in medical equipment such as hematology analyzers. Methods Failure data of five automated hematology analyzers (3-part differential) was collected over 14 consecutive months and a Weibull probability plot was made. The scale and shape parameters of this plot were used to predict failure probability distribution. This was then combined with various costs involved in remedial maintenance to get a cost analysis. Results The analyzers in their "useful life" period were found to suffer fewer actual and predicted failures compared to those in the "wear out" phase. Cost analysis showed a considerably higher per month cost of remedial maintenance of analyzers compared to the price of a comprehensive maintenance contract. Conclusions Our study demonstrates, for the first time, that Weibull distribution can be applied well to hematology analyzers for modeling of failure data and the resultant information is helpful in the cost analysis of maintenance to allow for prudent and informed decision making with regards to the mode of maintenance of analyzers.

Isolated Sternal Tuberculosis Presenting as a Chest Wall Abscess: A Case Report.

In India, pulmonary tuberculosis accounts for 85% of cases and extrapulmonary tuberculosis accounts for 15% of cases with bone and joint involvement is seen in 1 to 3% of cases. Primary tuberculous osteomyelitis of the sternum is a rare form of extrapulmonary tuberculosis. A 51-year-old male presented with 10 years history of swelling over the anterior chest wall and pain for past 6 months. Fine-needle aspiration cytology (FNAC) revealed a markedly granular necrotic background. Ziehl-Neelsen staining was positive for acid-fast bacilli and a diagnosis of the tubercular abscess was made. Chest X-ray was normal. Contrast-enhanced computed tomography was done, which gave an evidence of the erosion of the anterior surface of the sternum. Tuberculosis of the sternum is a rare form of flat bone tuberculosis. The possibility of sternal tuberculosis should be kept in mind in any patient with a mass, non-healing ulcer, or abscess in the sternal region.

Risk management in a clinical pathology laboratory: Application of brainstorming and probability analysis for risk reduction.

INTRODUCTION: Risk management includes identifying various risks, assessing the probability of occurrence, and evaluating the severity of their consequences. As clinical laboratories are integrally involved in patient care, risks in the laboratories could present grave consequences in some instances. This study aimed to utilize simple techniques for risk management in a clinical laboratory. MATERIALS AND METHODS: All potential risks in the pathology laboratory of a tertiary-level hospital were identified and classified into natural calamity, environmental, manpower-related, pre-analytical, analytical, post-analytical, and laboratory hazard-related risks through a brainstorming session. The probability of occurrence of each risk was estimated from departmental and hospital records. The possible impact of risk (score 1-10) was categorized into catastrophic, critical, serious, minor negligible, and insignificant. The unweighted risk score was calculated by multiplying the probability of occurrence and impact score. RESULTS: Inadequate sample-to-anticoagulant ratio had the highest probability of occurrence (22.85%), followed by quantity insufficient for analysis (7.30%) and laboratory information system (LIS) breakdown (6.58%). The highest unweighted risk score in our study was inadequate sample-to-anticoagulant ratio (score 91.40), followed by improperly labeled samples (score 35.61), manpower competency issues (score 32.88), sample insufficient for analysis (score 29.20), and LIS breakdown (score 26.30). CONCLUSION: We found that among all the categories, risks involving the pre-analytical phase had the highest risk scores. The other important risks included manpower competency issues requiring continued on-the-job training of staff as a risk reduction strategy. Brainstorming and probability analysis could be easily used for risk management in a clinical laboratory.

Perception of Current and Future Commitment of Medical Teachers to the Varied Roles of a Teacher: An Observational Study.

Background Medical education is gradually moving towards self-directed learning, thus the roles of a teacher have assumed wider dimensions than before. The awareness of these roles among medical teachers has been studied in several countries, but no study on the awareness of these roles among Indian medical faculty has been found. The aim of this research was to assess the current and future commitment perception of the roles of a teacher among Indian medical faculty. Methods A cross-sectional questionnaire-based survey regarding the 12 roles of a teacher, as defined by Harden and Crosby, was conducted among medical teachers in a tertiary-level hospital and medical college. The questionnaire consisted of three categories: importance in medical teaching, current commitment, and preferred future commitment to these roles, all measured on a five-point Likert scale. Results The highest mean scores were given to the roles of learning facilitator and on-the-job role model. In contrast, the lowest scores were designated to the production of study guides. Interestingly, the teachers' current commitment to roles such as curriculum planner and course organizer was found to be low. A significant difference was observed between the three categories for the majority of the roles. Younger faculties showed significant difference among categories, while the senior professors did not show significant variations across the roles. Conclusion This study of Indian medical teachers emphasizes the decreased importance attributed to roles like curriculum planning and course organization. Further studies in other developing countries are essential to understand this issue more comprehensively.

Expression of Epidermal Growth Factor Receptor (EGFR) and ß-catenin in Colorectal Carcinoma and its Correlation with Tumor Grade and Stage.

Colorectal cancer (CRC) is considered the result of the cumulative effect of multiple mutations within the cell that allow it to escape growth control and regulatory mechanisms. EGFR overexpression has been suggested as a factor of poor prognosis in various cancers. ß-catenin plays a role in the Wnt signaling pathway of colorectal cancers. An analytical cross-sectional study was conducted over a period of two years comprising 20 colectomy specimens. Clinicopathological details were documented, and immunohistochemistry (IHC) for EGFR and ß-catenin was performed. EGFR-Brown membranous staining was observed; ß-catenin-Brown membranous or nuclear staining was observed. IHC scoring was done, taking into account the intensity of staining and the percentage of positive tumor cells. The mean age of patients with colorectal carcinoma was 47.45 ± 14.8 (mean + SD) years. No statistically significant difference was noted in the EGFR immunoexpression and tumor grade (p value = 0.361) as well as the TNM stage (p value = 0.699). There was no statistically significant difference between ß-catenin immunoexpression and tumor grade (p value = 0.444) and TNM stage (p value = 0.911). A statistically significant difference was noted in the EGFR and ß-catenin immunoexpression (p = 0.0001). EGFR and ß-catenin expression was observed in 50% and 65% of cases, respectively. EGFR and ß-catenin expression was not associated with histological tumor grade and TNM stage of the tumor. In the present study, EGFR expression was significantly associated with ß-catenin immunoexpression.

Role of Red Cell Indices in Screening for Beta Thalassemia Trait: an Assessment of the Individual Indices and Application of Machine Learning Algorithm.

Antenatal screening for beta thalassemia trait (BTT) followed by counseling of couples is an efficient way of thalassemia control. Since high performance liquid chromatography (HPLC) is costly, other cost-effective screening methods need to be devised for this purpose. The present study was aimed at evaluating the utility of red cell indices and machine learning algorithms including an artificial neural network (ANN) in detection of BTT among antenatal women. This cross-sectional study included all antenatal women undergoing thalassemia screening at a tertiary care hospital. Complete blood count followed by HPLC was performed. Receiver operating characteristic (ROC) curve analysis was performed for obtaining optimal cutoff for each of the indices with determination of test characteristics for detection of BTT. Machine learning algorithms including C4.5 and Naïve Bayes (NB) classifier and a back-propagation type ANN including the red cell indices was designed and tested. Over a period of 15 months, 3947 patients underwent thalassemia screening. BTT was diagnosed in 5.98% of women on the basis of HPLC. ROC analysis yielded the maximum accuracy of 63.8%, sensitivity and specificity of 66.2% and 63.7%, respectively for Mean corpuscular hemoglobin concentration (MCHC). The C4.5 and NB classifier had accuracy of 88.56%-82.49% respectively while ANN had an overall accuracy of 85.95%, sensitivity of 83.81%, and specificity of 88.10% in detection of BTT. The present study highlights that none of the red cell parameters standalone is useful for screening for BTT. However, ANN with combination of all the red cell indices had an appreciable sensitivity and specificity for this purpose. Further refinements of the neural network can provide an appropriate tool for use in peripheral settings for thalassemia screening.

Optimization of Man Power Deployment for Covid-19 Screening in a Tertiary Care Hospital: A Study of Utility of Queuing Analysis.

OBJECTIVES: The recent Covid-19 pandemic has burdened the healthcare facilities, especially in the presence of limited infrastructure. We aimed at applying a queuing model to the Covid-19 screening area so as to optimize the screening services and ensuring that no patient is refused the service. METHODS: The mean arrival time of patients, number of physicians, mean screening time and queue characteristics were observed and entered in the M/M/c/K queuing model using R programming to optimize the number of physicians required in the screening area. RESULTS: Considering the mean arrival of 7 patients in 10 minutes and screening of 3 patients in 10 minutes by 1 physician, 2 physicians were assigned. At this capacity, the probability of saturation of the system was 15% with patient loss rate of 1.05 per 10 minutes. Queuing simulation with 3 physicians reduced the patient loss rate to 0.013 per 10 minutes and a saturation probability of 0.2%. However, an increase of arrival rate from 10 to 20 led to an early saturation of the system. CONCLUSION: Queuing models offer an opportunity for the healthcare providers and hospital administrators to optimize patient care services, especially in critical areas with an ever-changing situation such as the current pandemic.

The Milan System for Reporting Salivary Gland Cytopathology: An outcome of retrospective application to three years' cytology data of a tertiary care hospital.

OBJECTIVES: Fine-needle aspiration cytology (FNAC) of the salivary gland lesions has diverse and sometimes overlapping features that pose a diagnostic challenge for the cytopathologists. The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has been introduced to bring uniformity in the reporting of salivary gland FNAC and improve the clinic-pathologic communication resulting in better patient management. The aim of the present study was to assess the application of the MSRSGC on FNAC specimens of salivary gland lesions at a tertiary care hospital. MATERIAL AND METHODS: All salivary gland aspiration cytology cases along with histopathology follow-up of salivary gland lesions, wherever available, over a period of 36 months were analyzed and re-categorized according to MSRSGC into six categories and the risk of malignancy (ROM) was computed. RESULTS: Of the 123 patients, 23 (18.69%) were classified as non-diagnostic, 39 cases (31.7%) as non-neoplastic, one (0.81%) as atypia of undetermined significance (AUS), benign neoplasm in 49 (39.8%) cases, uncertain malignant potential in two cases (1.63%), suspicious of malignancy in two cases, and malignant in seven cases (5.69%). Out of 123 cases, histopathological correlation was available in 34 cases, for which the ROM was calculated. The ROM was 0% for non-neoplastic, 11.1% for benign neoplasm, and 100% each for salivary neoplasm of uncertain neoplastic potential, and 100% for malignant categories. CONCLUSION: In the present study, the distribution of cases according to MSRSGC was comparable with the previous studies. The proportion of cases classified as AUS was within the goal set by MSRSGC at less than 10%. A risk-based stratification of salivary gland lesions in the form of MSRSGC is essential in the present era to guide and alert the clinician about the subsequent management plan and convey the ROM.

A case report of small round cell tumor of palm: A difficult code to decipher on cytology.

INTRODUCTION: Small round cell tumors (SRCT) are difficult to sub categorise on fine-needle aspiration cytology (FNAC) samples as they are rare and it is difficult for cytopathologists to obtain enough experience for rendering reliable diagnoses. Various sub categories of SRCTs are morphologically very similar. Many SRCTs do not have specific antigens which could be demonstrated with immunocytochemistry (ICC) or they lose them when poorly differentiated. Besides, cross-reactivity exists between some SRCTs. Suboptimal FNAC sampling from a heterologous component and unstandardized performance of ICC contributes to the pitfalls. PRESENTATION OF THE CASE: A 40-year-old male presented with a swelling measuring 3 cm in diameter on palmar aspect of right-hand. Magnetic resonance imaging suggested cyst of tendon sheath. However, on cytology in combination with ICC, a diagnosis of non-lymphoid small round cells tumor was suggested, with confirmatory diagnosis on histopathology. CONCLUSION: FNAC assisted with ICC can be a rapid and economical diagnostic tool in cases of high-grade malignant tumors for which early diagnosis is extremely important.

Comparison of asynchronous and synchronous methods of online teaching for students of medical laboratory technology course: A cross-sectional analysis.

BACKGROUND: In the wake of the novel coronavirus pandemic, the closure of educational institutions has imposed a situation of potential gap in learning. Since training of medical and paramedical students is vital in creation of our army of these frontline health-care workers, this study was aimed at comparing the asynchronous and synchronous methods of online teaching for imparting training to students of medical laboratory technology (MLT). MATERIALS AND METHODS: This cross-sectional study included 33 students of the 1st-year batch of MLT course at a tertiary level hospital. Ten lectures each from the subject of biomedical statistics were delivered through asynchronous (lecture shared on WhatsApp group) and synchronous (online live lecture) methods followed by a brief examination for each topic. A short survey was designed to assess the students' perception of clarity of concepts, confidence of solving the examination, and their preference for one of these methods. Appropriate statistical tests were applied to the data. RESULTS: Synchronous method of online teaching was preferred by majority of the students (P < 0.001). Students' clarity in understanding of the concepts (P < 0.001) and confidence of the ability to solve examination questions (P < 0.05) was higher after synchronous teaching. The examination scores after synchronous online teaching were significantly higher (P = 0.0156) than those for topics covered through asynchronous method. CONCLUSION: Online teaching, especially the synchronous method, offers an opportunity of continuum of training during crisis situations such as the ongoing novel coronavirus pandemic. The wide availability of internet services and the ever-changing global situation mandates readiness for this modality of teaching, both for the teachers and the students.

Codetection of pulmonary tuberculosis and toxoplasmosis in a pediatric bronchoalveolar lavage specimen: A cytologist's assistance to clinical management.

BACKGROUND: Toxoplasmosis causes serious and sometimes life-threatening disease in immunocompromised patients like organ transplant recipients, immunodeficiency disorders or HIV-infected individuals. The co-occurrence of toxoplasmosis in a respiratory sample harboring tuberculosis (TB) may be missed especially in an area endemic for the latter infection. CASE REPORT: A 10-year-old child presented with complaints of fever with loss of appetite and weight. Based on radiological and clinical features, a presumptive diagnosis of pulmonary TB was made and bronchoalveolar lavage (BAL) performed for cytological and microbiological confirmation. Smears from BAL showed numerous lymphocytes along with few ciliated columnar epithelial cells. Ziehl-Neelsen stain for acid-fast bacilli was positive. The Giemsa-stained cytosmears also showed clusters of crescent-shaped tachyzoites of toxoplasma gondii in a background of lymphocytes. The patient was initiated on anti-tubercular therapy with marked clinical improvement. CONCLUSION: A diligent screening of cytosmears for a possible coinfection in a TB-positive sample is essential for the cytopathologists to detect coexisting toxoplasmosis, which is a rare but treatable disease.

Incidental detection of microfilaria in cyst fluid of Mucinous cystadenocarcinoma of ovary: A rare case report.

INTRODUCTION: Filariasis is a major health problem in certain parts of India. Microfilaria detection on exfoliative and fluid cytology is extremely rare and it is even very rare to find microfilaria coexistent with neoplastic lesions. PRESENTATION OF CASE: A 45-year-old nulliparous female, who presented with complaints of lower abdominal swelling and pain. Initially, a clinical diagnosis of cystadenoma was made. Ascitic fluid cytology of the patient showed 3-dimensional clusters of cells along with an occasional microfilaria. On histopathology, a diagnosis of Mucinous cystadenocarcinoma of ovary was made. DISCUSSION: Most common cause of lymphatic filariasis is W. bancrofti followed by Brugia species and it affects young adults. The adult form of the filaria lodge in lymph vessels, and due to lymphatic blockage in neoplasms they appear in tissue fluid or on surface material. It is the first case report of microfilaria being detected in ovarian cystic fluid cytology in a patient of Mucinous cystadenocarcinoma of ovary. CONCLUSION: Filaria is an incidental finding in most of the cases, hence, cytopathologist should be vigilant and careful screening of all the slides should be done, especially in a country like India, where it is highly endemic.

Middle ear adenoma with neuroendocrine differentiation: Report of a rare case.

Middle ear adenoma with neuroendocrine differentiation (MEA-ND) is also called as neuroendocrine adenoma. Neuroendocrine tumors are rarely seen in the head and neck region and are even more rare in the middle ear. Clinical and radiological findings are non-specific and seldom suggest this diagnosis. Nomenclature and behavior of this tumor has been historically controversial. Both epithelial as well as neuroendocrine origin have been suggested. They comprise <2% of all ear tumors and commonly present with unilateral hearing loss, aural fullness, and tinnitus. We present a case report of MEA-ND in a 24-year-old woman who presented with heaviness and tinnitus in the right ear.

Immunoexpression of estrogen receptor-ß and progesterone receptor in prostate adenocarcinoma, does it inhibit neoplastic proliferation and invasion?

CONTEXT: The roles of estrogen and progesterone in human prostate carcinogenesis have been only recently recognized. AIMS: This study was conducted to evaluate the expressions of esterone receptor-beta (ER-ß), progesterone receptor (PR), and Ki-67 in benign and malignant lesions of the prostate. SETTINGS AND DESIGN: The study was conducted at a tertiary care hospital. It was an analytical cross-sectional study. MATERIALS AND METHODS: We selected a total of 39 cases including 26 cases of benign prostatic hyperplasia and 13 cases of adenocarcinoma prostate. The proportion of cases showing expression for ER-ß, PR, and Ki-67 was noted for both groups. A difference in immunoexpression between benign and malignant cases was evaluated. Association between receptor expression and Gleason grade was evaluated for malignant cases. STATISTICAL ANALYSIS USED: To compare the difference in expressions of ER-ß, PR, and Ki-67 Mann-Whitney U test was used. Association between ER-ß, PR, and Ki-67 expression and Gleason grade was analyzed using the Chi-square test. RESULTS: ER-ß expression was seen in all benign and malignant cases, whereas the majority of the malignant cases (61.54%) were negative for progesterone expression. Epithelial expressions of ER-ß and PR were significantly higher in benign as compared with malignant lesions. Malignant cases showed a significantly higher expression of Ki-67. However, we did not find any association between the expressions of these markers with Gleason grade. CONCLUSIONS: The expressions of ER-ß and PR were significantly higher in the epithelium in benign cases as compared with malignant cases. Ki-67 expression was significantly higher in the malignant group as compared with the benign group.

Chronic calculus cholecystitis: Is histopathology essential post-cholecystectomy?

BACKGROUND: Carcinoma of the gall bladder (GB) is the most common malignancy of the gastrointestinal tract. One percent of cholecystectomy specimens show incidental gall bladder cancers (GBCs). AIM: Our aim of the study to was evaluate the utility of routine histopathology of cholecystectomy specimens removed with a diagnosis of gall bladder diseases (GBD). MATERIALS AND METHODS: A retrospective study was done reviewing the histopathological records of 906 patients who underwent cholecystectomy. Demographic details, gross findings, and microscopic findings noted. All the cases were categorized into two groups, A and B. Group A included the cases with any gross abnormality including wall thickness ≥4 mm and group B included rest of the cases. RESULTS: Majority of the patients were in the age group of 31-40 years of age. Out of 906 patients studied, majority of them were females with F:M ratio of 6.14:1. Of the 47 cases which were included in group A (with macroscopic abnormality), six cases had gall bladder carcinoma on microscopy. One case from group B with macroscopically normal-appearing GB had invasive carcinoma on microscopy. In our study, we found a sensitivity of 85.71% and specificity of 95.44%, while positive predictive value (PPV) was 91.11% and negative predictive value (NPV) was 99.65% of macroscopic abnormality in the diagnosis of invasive carcinoma. CONCLUSION: All cholecystectomy specimens must be examined by histopathologists who must decide whether processing for microscopy is needed. Microscopic examination may be reserved for the specimen with a macroscopic lesion. This will result in a reduction of costs and pathology workload without compromising patient management.

Nerve Sheath Myxoma of Scalp: A Rare Site of Presentation.

Nerve sheath myxoma, a superficial myxoid tumor, was first described in 1969 by Harkin and Reed. Tumor has cytological and histological resemblance with neurothekeoma, another cutaneous myxoid lesion. Nerve sheath myxoma affects individuals of all age groups and equal predilection for both genders with most favored sites being the fingers and knee. Here, we present a case report of nerve sheath myxoma of the scalp, diagnosed and confirmed with histopathology and immunohistochemistry.

Eruptive Vellus Hair Cyst: An Uncommon and Underdiagnosed Entity.

Eruptive vellus hair cyst (EVHC) is a rare follicular developmental abnormality of the vellus hair follicles. They are usually seen in children, adolescents, or young adults and manifest as reddish-brown smooth papules most commonly involving the chest, limbs, and abdomen. An 18-year-old male presented with asymptomatic papules on the trunk and flexor aspect of both forearms for the past 2 years. There was no family history of similar lesions. His medical history was also not contributory. A clinical diagnosis of steatocystoma multiplex and chronic folliculitis was given, and a punch biopsy from the papule was performed and sent for histopathological examination. On microscopic examination, a final diagnosis of EVHC was rendered. The patient was advised topical treatment of retinoic acid cream (0.05%) for 6 months, and he is currently under follow-up period. Due to its rarity and resemblance to many similar entities, histopathological examination plays a major role in establishing a definite diagnosis and further proper management of the patient. We report this unusual case to generate awareness about this rarely diagnosed condition.

Malignant Phyllodes tumor in a young female: A Case Report.

Phyllodes tumor is a rare fibroepithelial neoplasm of the breast and constitutes 0.3-0.5% of all breast tumors. They are usually benign and only few of them undergo malignant transformation. Benign or borderline phyllodes tumor typically never recur however, malignant phyllodes tumors do have a recurrence and a metastatic potential. Differentiating these two groups is of prime importance for proper management of the patient. We report a rare case of Malignant Phyllodes tumor in an 18 year old female. She presented with a left breast lump which was gradually increasing in size. There was no significant past or family history. Physical examination revealed a 10x10 cm mass which involved the entire left breast. There was no axillary or supraclavicular lymphadenopathy. On fine needle aspiration cytology, a diagnosis suggestive of an atypical cytology (C3) was given and patient was advised to undergo urgent biopsy and on histopathological examination a possibility of malignant phyllodes tumor was rendered. Following this, lumpectomy was performed and a diagnosis of Malignant Phyllodes tumor was confirmed. Within two months of surgery patient had a recurrence of a huge breast lump with overlying skin ulcerations and underwent a left simple mastectomy. Patient is currently under follow up period and free of disease. A definitive preoperative diagnosis is of utmost importance in correct surgical management of the patient and in order to avoid local recurrences.

Intussusception caused by heterotopic gastric mucosa in small intestine: a case report.

BACKGROUND: Intestinal intussusception is the most frequent cause of small bowel obstruction in children between the ages of 2 months and 5 years and often remains idiopathic in etiology, even after surgery. On microscopic examination, in intussusception normal mucosa is noted but in a few cases heterotopic tissue can be seen. Heterotopic gastric mucosa in the small intestine is extremely rare except for its occurrence in remnants of Meckel's diverticulum. In view of the rarity of this condition, we report a case of ectopic gastric mucosa in the small intestine that was not associated with remnants of vitelline duct. CASE PRESENTATION: A 6-year-old boy of Indo-Aryan ethnicity from India presented with episodes of acute abdominal pain and distension with vomiting and non-passage of stools. On ultrasonography intussusception was suspected. A laparotomy was done and the ileal segment (tip of intussusception) was sent for histopathological examination. On histopathology, sections from the tip of intussusception showed extensive gastric metaplasia of the mucosa. CONCLUSIONS: A definitive diagnosis of heterotopic gastric mucosa is established by histopathological examination and it is important to differentiate heterotopia, which is a developmental anomaly, from metaplasia, which is an acquired condition. Heterotopic gastric mucosa is usually clinically silent and surgical intervention can be considered in patients with complications such as gastrointestinal hemorrhage and intestinal obstruction.