Jaya Ruth Asirvatham

Errors in Potassium Measurement: A Laboratory Perspective for the Clinician

Errors in potassium measurement can cause pseudohyperkalemia, where serum potassium is falsely elevated. Usually, these are recognized either by the laboratory or the clinician. However, the same factors that cause pseudohyperkalemia can mask hypokalemia by pushing measured values into the reference interval. These cases require a high-index of suspicion by the clinician as they cannot be easily identified in the laboratory. This article discusses the causes and mechanisms of spuriously elevated potassium, and current recommendations to minimize those factors. “Reverse” pseudohyperkalemia and the role of correction factors are also discussed. Relevant articles were identified by a literature search performed on PubMed using the terms “pseudohyperkalemia,” “reverse pseudohyperkalemia,” “factitious hyperkalemia,” “spurious hyperkalemia,” and “masked hypokalemia.”

Rotavirus Infection in the Neonatal Nurseries of a Tertiary Care Hospital in India

Background: The majority of neonatal rotavirus infections are believed to be asymptomatic, and protection from subsequent infection and disease has been reported in neonatally infected children. In this study, we present the results of a 4-year prospective surveillance in the neonatal nurseries of a tertiary care hospital in south India. Methods: Stool samples from neonates admitted for >48 hours either with gastrointestinal (GI) symptoms or with nonenteric pathology were screened for rotavirus. Careful assessment of clinical data was carried out. G- and P-typing for all symptomatic rotavirus positive cases and equal number of asymptomatic controls from the same month was determined by reverse transcription polymerase chain reaction. Results: Rotavirus was detected in 43.9% of 1411 neonates, including those with and without gastrointestinal disease. Rotavirus detection was significantly higher among neonates with GI disease (55.5%) than asymptomatic neonates (44.4%) (P < 0.001). Rotavirus was seen in association with diarrhea, vomiting, feed intolerance, necrotizing enterocolitis, hematochezia, gastroesophageal reflux, and abdominal distension. Diarrhea was significantly more frequent in neonates with rotavirus infection (P < 0.001) whereas uninfected neonates developed significantly more feeding intolerance (P < 0.001). Significantly greater proportion of term neonates with GI disease were positive for rotavirus than preterm neonates (P < 0.001). G10P[11] was the most common genotype associated with both symptomatic and asymptomatic infections. Conclusions: This study documents the high rates of rotavirus infection in the neonatal nurseries and the continuing detection of the G10P[11] strain associated with GI disease in Vellore.

Estimates of the economic burden of rotavirus-associated and all-cause diarrhoea in Vellore India.

Objective  To determine the cost of rotavirus and all‐cause diarrhoea in Vellore, India.

Role of PAX-8, CD5, and CD117 in distinguishing thymic carcinoma from poorly differentiated lung carcinoma.

Aim:To determine if PAX-8, CD5, and CD117 can differentiate thymic carcinoma from poorly differentiated lung carcinoma. Design:Archived cases of thymic (n=13) and poorly differentiated lung (n=15) carcinoma were analyzed for intensity and proportion of expression of PAX-8, CD117, and CD5. Results:PAX-8 was positive in 69.2% of thymic and 5.8% of lung carcinomas. CD117 was positive in 84% of thymic and 26.6% of lung carcinomas. A total of 53% of thymic and none of the lung carcinomas were positive for CD5. Forty-six percent, 53%, and 69% of thymic carcinomas were dual positive for combinations of CD5/PAX-8, CD117/CD5, and CD117/PAX-8, respectively. None of the lung carcinomas were dual positive. Positivity for any 2 of the 3 markers was seen in 84% of thymic and none of the lung carcinomas. Triple positivity was seen in 53% of thymic carcinomas. Conclusion:Adding PAX-8 to CD117 and CD5 increases the diagnostic yield for thymic carcinoma.

Ossifying Fibromyxoid Tumor of the Breast Mimicking Fibroadenoma: A Case Report and Differential Diagnoses

An 80-year-old woman presented with a palpable mass in the right breast. Mammographic findings were consistent with calcified fibroadenoma. An ultrasound was performed that showed a solid nodule with peripheral calcification. A core biopsy was obtained that revealed a spindle cell proliferation with a shell of mature bone. The histologic features, in combination with immunohistochemical studies, were those of an ossifying fibromyxoid tumor. Complete excision of the specimen further confirmed the diagnosis. To the best of our knowledge, this is the first reported case of ossifying fibromyxoid tumor occurring in the breast. We review the current literature on ossifying fibromyxoid tumor and discuss the differential diagnoses when confronted with bland spindle cells on a core biopsy of the breast.

Beta-human chorionic gonadotropin producing osteosarcoma of the sacrum in a 26-year-old woman: a case report and review of the literature.

Ectopic secretion of beta-human chorionic gonadotropin is considered a poor prognostic marker in epithelial tumors. However, very few cases have been reported in sarcomas. We present the case of a 26-year-old female who presented with a metastatic osteosarcoma. She underwent usual testing prior to starting treatment and was found to have elevated levels of beta-human chorionic gonadotropin. As the patient was not pregnant, another source of beta-human chorionic gonadotropin secretion had to be considered. The tumor cells demonstrated positive staining for beta-human chorionic gonadotropin by immunohistochemistry, and serum levels of beta-human chorionic gonadotropin were used to monitor tumor progression and response to chemotherapy. We review the literature and discuss a potential role of beta-human chorionic gonadotropin in the treatment of such patients.

Atypical Apocrine Adenosis: Diagnostic Challenges and Pitfalls

Apocrine change in the breast is an extremely common finding. In most cases, the benign or malignant nature of the lesion is easily recognized. Apocrine adenosis is used to describe sclerosing adenosis with apocrine change. The term apocrine atypia is used when there is significant cytologic atypia in apocrine cells, characterized by a 3-fold nuclear enlargement, prominent/multiple nucleoli, and hyperchromasia. Atypical apocrine adenosis is diagnosed when apocrine adenosis and apocrine atypia are superimposed. However, there are no definite criteria to distinguish atypical apocrine adenosis from apocrine ductal carcinoma in situ. Immunohistochemical markers can be confounding and may lead to erroneous diagnoses. Atypical apocrine features in sclerosing lesions may be misinterpreted as invasive carcinoma if the underlying lesion is not recognized. In the absence of definite features of malignancy, the diagnosis of apocrine ductal carcinoma in situ may be extremely difficult. In the present article, we review atypical apocrine adenosis focusing on diagnostic challenges and their implications on clinical management.

Molecular characteristics of meningiomas in a cohort of Indian patients: loss of heterozygosity analysis of chromosomes 22, 17, 14 and 10.

BACKGROUND Though, loss of heterozygosity (LOH) at chromosome 22q is considered to be the most likely initiating event in the formation of meningiomas, LOH at other chromosomes (1, 3, 6, 9, 10, 11, 14.17, and 18) have been implicated in its progression. The aim of this study was to analyze microsatellite markers on a select set of chromosomes including, 22q, 10q, 14q, and 17p for LOH in patients with meningiomas. MATERIALS AND METHODS Tumor tissue and its corresponding blood sample were collected from 27 patients with meningioma. Four polymorphic microsatellite markers (D10S520, D17S1289, D14S555, and D22S417) were characterized for LOH analysis. RESULTS There were 14 World Health Organization (WHO) grade I, 12 WHO grade II and 1 WHO grade III meningiomas. LOH was seen most often at D22S417 with an equal distribution between the grades (33% of informative samples in each grade). Though, LOH at D14S555 was seen in 50% of informative WHO grade II tumors, compared to 11.1% of informative WHO grade I tumors it did not reach statistical significance. However, allelic imbalance (AI) at D14S555 was significantly associated with atypia (P = 0.05). LOH at D17S1289 was seen only in one tumor sample, and none of the informative samples displayed LOH at D10S520. CONCLUSION The frequency and equal distribution of LOH at chromosome 22 supports the hypothesis that it is an early event in the tumorigenesis of meningiomas. The association of AI at D14S555 in WHO grade II meningiomas needs to be investigated on a larger set of samples.

Kikuchi-Fujimoto Disease Masquerading as Metastatic Papillary Carcinoma of the Thyroid

Kikuchi-Fujimoto disease also known as histiocytic necrotizing lymphadenitis is a rare cervical inflammatory lymphadenitis that is most commonly seen in young Asian women. It is mainly characterized by lymphadenopathy, hepatosplenomegaly, fever, nocturnal sweats, myalgia, weight loss, and arthralgia, and commonly follows a self-limited course. The differential diagnosis is challenging as many other conditions such as malignant lymphoma, metastatic disease, tuberculosis and infectious lymphadenopathies can present in a similar way. We present an unusual case of Kikuchi-Fujimoto disease masquerading as metastatic papillary carcinoma of the thyroid. A 30-year-old young female presented, 2 months post-partum, with complaints of neck pain and fever. A computed tomography scan showed enlarged right-sided lymph nodes and a thyroid nodule. Subsequent biopsy of a thyroid nodule revealed papillary thyroid carcinoma and reactive inflammation in one of the lymph nodes. She underwent an elective total thyroidectomy, central node dissection and a right modified lymph node dissection for enlarged lymph nodes. Her recovery was uneventful and the pathology report was consistent with a papillary carcinoma of the thyroid with one lymph node positive for metastatic disease and several other lymph nodes showing histiocytic necrotizing lymphadenitis. This coexistence of Kikuchi-Fujimoto disease with localized metastatic papillary thyroid cancer is unusual and presents an interesting, challenging, and complex management dilemma.

Epithelioid hemangioendothelioma involving bone marrow presenting with persistent anemia

A 54-year-old man presented with persistent anemia (hemoglobin ranging from 7.6 to 9.5 g/dl), fever, and night sweats. Imaging studies showed multiple liver and bilateral pulmonary nodules, numerous small lucent lesions throughout the thoracic spine, and a destructive right seventh posterior rib lesion. Laboratory testing showed iron deficiency anemia with a component of anemia of chronic disease (iron: 22 mg/dl, ferritin 609 ng/ml, soluble transferring receptor 9.0 mg/l) with mildly elevated lactate dehydrogenase (399 U/l) and negative direct antiglobulin test. Blood cultures (including fungal and acid fast bacilli) were negative and white blood cell counts were within the reference range. Though human immunodeficiency virus testing was not performed, flow cytometry showed a normal CD4/CD8 ratio. The serum electrophoresis pattern was reported as consistent with acute inflammation or a stress response, and erythrocyte sedimentation rate was 105 mm/hr. Bone marrow biopsy showed marrow infiltration by a vascular proliferation characterized by slightly spindled epithelioid cells forming nests and few distinct vascular channels, filled with blood (Fig. 1A). Miniature intracytoplasmic lumina containing red blood cells (Fig. 1B) were evident in some epithelioid cells. There were no atypical features such as high mitotic activity or cellular pleomorphism. The neoplastic cells were positive for CD34 (Fig. 1C), CD31, Factor VIII, and smooth muscle actin (Fig. 1D) and negative for HHV8-LANA by immunohistochemistry, which together with the histology confirmed the diagnosis of epithelioid hemangioendothelioma, a malignant angiocentric vascular tumor. There was no evidence of hemophagocytosis in the smear or bone marrow biopsy. A subsequent liver biopsy was also performed which supported the diagnosis. Epithelioid hemangioendothelioma usually presents as a superficial or deep soft tissue mass. About half the cases are associated with or arise from a vein. Metastases are usually to lymph nodes, lung, liver, and bone and are usually seen in tumors with atypical features. A small portion of benign appearing epithelioid hemangioendotheliomas do metastasize. However, involvement of the bone marrow is very rare. The epithelioid nature of some vascular neoplasms such as the current case or epithelioid angiosarcoma can pose diagnostic difficulties due to the abundant cytoplasm and positivity for immunomarkers indicative of epithelial origin such as cytokeratin, bringing into the differential metastatic carcinoma, melanoma, large cell lymphoma, and other epithelioid sarcomas. Vascular neoplasms can also present with hematologic abnormalities such as thrombocytopenia, disseminated vascular coagulation causing Kasabach–Merritt syndrome, autoimmune and microangiopathic hemolytic anemia, Evans syndrome, hyposplenism, and rarely erythrophagocytosis [1–5].