Endobronchial Glandular Papilloma With Atypical Histologic Characteristics: A Case Report and Literature Review.

Papilloma of the lung is a rare benign entity and can be solitary or multiple. Solitary papilloma is subclassified into three categories: squamous papilloma, glandular papilloma, and mixed squamous and glandular papilloma. Glandular papilloma is the rarest subtype among them and occurs mostly in the sixth decade without any relation to smoking, syndrome, or infection. Histology is characterized by mixture of pseudostratified, columnar, nonciliated, mucinous epithelium-lined papillary fronds without any mitoses, necrosis, or atypia. The differential diagnosis can be broad depending upon the histologic features present in a particular case and may include both benign and malignant entities. We present here a patient with glandular endobronchial papilloma showing unusual clinical history and atypical histologic features, which required extensive immunohistochemical evaluation to establish a final diagnosis.

Cardiac macrophage density in Covid-19 infection: relationship to myocyte necrosis and acute lung injury.

SARS-Cov-2 infection is not limited to the respiratory tract and can involve other organs including the heart, blood vessels, kidneys, liver, gastrointestinal tract, placenta, and skin. Covid-19 patients with cardiac involvement usually have higher morbidity and mortality compared to those without cardiac involvement. The frequency and the specificity of the myocardial pathological changes in patients who die after documented infection with SARS-Cov-2 is uncertain. Macrophages can be found in the normal heart (interstitium, around the endothelial cells and in the epicardial adipose tissue), and they are considered part of the major immune cell population in the heart. In this case-control autopsy study, we compare the gross and microscopic cardiac findings, and the available clinical characteristics between a group of 10 Covid-19 decedents and a control group of 20 patients who died with non-SARS-Cov-2 severe bronchopneumonia and/or diffuse alveolar damage. The objectives of this semi-quantitative study are to study single myocyte necrosis and its relation to the strain on the heart caused by lung injury as a causative mechanism, and to study the density of myocardial and epicardial macrophages in Covid-19 hearts in comparison to the control group, and in Covid-19 hearts with single myocyte necrosis in comparison to Covid-19 hearts without single myocyte necrosis. Lymphocytic myocarditis was not identified in any of the hearts from the Covid-19 or the control group. Single myocyte necrosis is more frequent in the Covid-19 group compared to the control group, suggesting that it is unrelated to the strain on the heart caused by underlying lung injury. The density of the macrophages in the epicardium and myocardium in the hearts of the Covid-19 group is higher compared to those in the control group. The density of epicardial macrophages is higher in the Covid-19 hearts with single myocyte necrosis than in those without. These observations contribute to our increasing appreciation of the role of macrophages in the pathophysiologic response to infection by SARS-CoV-2.

A perplexing airspace: peace of mind now or later.

A perplexing right middle lobe lesion in a young woman. Peace of mind now or later? https://bit.ly/3veB5wE.

Neuroendocrine Neoplasia in Extranodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT Lymphoma) of the Lung: A Case Report and Immunohistochemistry Analysis of Eight Pulmonary MALT Lymphomas.

Carcinoid tumorlets are peribronchiolar proliferations of neuroendocrine cells often associated with lung scars. Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is a non-Hodgkin's lymphoma that frequently involves the gastrointestinal tract but less commonly is described in the lung. Simultaneous occurrence of neuroendocrine neoplasms and MALT lymphoma is extraordinarily rare and has predominately been reported in the gastrointestinal tract. In this article, we describe the case of a 73-year-old female with coexisting pulmonary MALT lymphoma and carcinoid tumorlets of the right middle lobe. Retrospective series of 8 pulmonary MALT lymphomas are evaluated for neuroendocrine neoplasia by immunohistochemistry. No correlation between MALT lymphoma and neuroendocrine neoplasia was identified in this case series. While the concurrence of these distinctive neoplasms is most likely coincidental, the presence of a common risk factor, or one neoplasm as a risk factor for the other, deserves study of a larger group of pulmonary MALT lymphomas.

The diagnostic value of the ThinPrep pap test in endometrial carcinoma: a prospective study with histological follow-up.

Case-control studies have demonstrated that the ThinPrep Pap test may provide improved detection of endometrial carcinoma. The purpose of this study is to prospectively examine the diagnostic potential of the ThinPrep Pap test in the detection of endometrial carcinoma. ThinPrep Pap test slides were collected from high-risk patient groups. Pap-stained slides were reviewed and the cytological diagnosis was rendered independently by investigators. Each case was assigned to one of the four diagnostic categories: within normal limit (WNL); atypical glandular cells (AGC); atypical endometrial cells (AEC); or adenocarcinoma, probably endometrial origin. After cytological diagnosis was made, the histological follow-up diagnosis was obtained through the laboratory information system and the cyto-histological correlation was analyzed. Of 106 patients identified, 60 had histological follow-up. For all eight cases interpreted by cytology as positive, endometrial carcinoma was confirmed histologically. Among 25 patients with normal endometrial cells present, histological follow-up showed benign endometrium. Among 17 cases interpreted cytologically as AEC, 14 cases (82.4%) had benign histological follow-up and 3 cases (17.6%) had endometrial carcinoma. All 11 cases (100%) classified as AGC had benign histological follow-up. The sensitivity and specificity of detecting endometrial malignancy were 72.7% and 100%, respectively. The positive predictive value was 100%. In this prospective study, we demonstrated that the Thin Prep Pap test had a reasonably high sensitivity and/or specificity in detecting endometrial carcinoma.

Short-term exposure to tobacco toxins alters expression of multiple proliferation gene markers in primary human bronchial epithelial cell cultures.

The biological effects of only a finite number of tobacco toxins have been studied. Here, we describe exposure of cultures of human bronchial epithelial cells to low concentrations of tobacco carcinogens: nickel sulphate, benzo(b)fluoranthene, N-nitrosodiethylamine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). After a 24-hour exposure, EGFR was expressed in cell membrane and cytoplasm, BCL-2 was expressed only in the irregular nuclei of large atypical cells, MKI67 was expressed in nuclei with no staining in larger cells, cytoplasmic BIRC5 with stronger nuclear staining was seen in large atypical cells, and nuclear TP53 was strongly expressed in all cells. After only a 24-hour exposure, cells exhibited atypical nuclear and cytoplasmic features. After a 48-hour exposure, EGFR staining was localized to the nucleus, BCL-2 was slightly decreased in intensity, BIRC5 was localized to the cytoplasm, and TP53 staining was increased in small and large cells. BCL2L1 was expressed in both the cytoplasm and nuclei of cells at 24- and 48-hour exposures. We illustrate that short-termexposure of a bronchial epithelial cell line to smoking-equivalent concentrations of tobacco carcinogens alters the expression of key proliferation regulatory genes, EGFR, BCL-2, BCL2L1, BIRC5, TP53, and MKI67, similar to that reported in biopsy specimens of pulmonary epithelium described to be preneoplastic lesions.

The Movat pentachrome stain as a means of identifying microcrystalline cellulose among other particulates found in lung tissue.

CONTEXT: Microcrystalline cellulose (MCC) is extensively used as a filler material in pharmaceutical tablets. When injected intravenously in aqueous tablet suspensions, MCC may contribute to embolic pulmonary hypertension and be identified histologically in lung tissue samples. In this study, we evaluated a modified Russell Movat pentachrome stain (MMPS) as a means of recognizing MCC and distinguishing it from other birefringent crystals in lung specimens. OBJECTIVE: To study the staining properties of MCC versus other crystalline materials using the MMPS stain. DESIGN: Archival, formalin-fixed, paraffin-embedded lung specimens that contained birefringent crystals, including MCC (3 cases of intravenous drug abuse), talc (2 cases of intravenous drug abuse, 1 talc pleurodesis), mixed silicates (1 case of silicate pneumoconiosis), and calcium oxalate (1 case of aspergillosis from Aspergillus niger infection), were evaluated with MMPS. Crystal identification was confirmed by morphology, other histochemical stains, infrared spectroscopy (1 case), and cellulose controls. RESULTS: The MMPS stained the MCC bright yellow in tissue and control specimens. Talc stained light greenish-blue; mixed silicates appeared either greenish-blue or unstained. Oxalate crystals stained sea-green. Crospovidone, a nonbirefringent tablet filler substance, stained yellow to dark green with MMPS and was easily distinguished from MCC. Starch granules were unstained by MMPS. CONCLUSIONS: The MMPS is an excellent method for the histochemical identification of MCC in tissue and its separation from other birefringent crystals with which MCC might be confused. The MMPS is especially useful in the evaluation of pulmonary foreign body embolization in cases of suspected intravenous substance abuse.

Smoking-related interstitial lung disease.

Pulmonary diseases associated with tobacco smoking are a complex group of disorders ranging from chronic obstructive pulmonary disease (COPD) to lung cancer. Interstitial lung diseases (ILDs) have only recently been linked to smoking. The ILDs related to smoking include respiratory bronchiolitis-associated interstitial lung disease, desquamative interstitial pneumonia, and pulmonary Langerhans cell histiocytosis. The relationship of smoking with each of these entities has been largely established on the weight of epidemiologic evidence. Although they have been retained as distinct and separate conditions in various classifications of interstitial lung diseases, these 3 entities share a number of clinical, radiologic, and pathologic features suggesting that they represent a spectrum of patterns of interstitial lung disease occurring in predisposed individuals who smoke. Evaluation of histologic features, particularly in surgical lung biopsy samples, is important in making the distinction between these disorders. However, even after tissue biopsy, it may sometimes be difficult to clearly separate these entities. The importance of making the distinction between them lies in the different clinical management strategies used. Further experimental evidence, including genetic information, may be important in improving our understanding of these diseases.

Lymphocyte sub-populations and non-Langerhans' cell monocytoid cells in pulmonary Langerhans' cell histiocytosis.

Pulmonary Langerhans' cell histiocytosis (PLCH) is a disease characterized by the occurrence of complex fibro-cellular interstitial lesions dominated by Langerhans' cells (LC), which occurs predominantly in young adult smokers. We undertook this retrospective study to better define the lymphohistiocytic cell populations in PLCH in order to obtain a greater insight into its pathogenesis. Formalin-fixed, paraffin-embedded, surgically excised, archival lung tissue from seven patients (two males, five females; average age 34.9 years) was immunostained with a panel of antibodies for lymphohistiocytic markers: CD1a, CD3, CD4, CD8, CD15, CD20, CD56, TIA-1, CD68-PGM1, Mac387, and mast cell tryptase. Double immunolabeling was performed with CD1a/Mac387. Leder cytochemical stain for chloroacetate esterase was also performed. A moderate number of lymphocytes, predominantly T lymphocytes, were scattered diffusely within the lesions. The mean CD4/CD8 ratio was 0.1/1. The CD3/CD8 ratio (1.18/1) substantiated the CD4/CD8 ratio. The CD8 subset was CD56-negative and TIA-1-positive, indicating a cytotoxic T lymphocyte phenotype. CD68-PGM1 was strongly positive in alveolar macrophages (AM) and weakly stained LC. Mac387, a marker of activated macrophages, weakly stained AM, while highlighting other interstitial cells. These interstitial cells appeared not to be LC (substantiated by CD1a/Mac387 dual labeling) or CD68-PGM-1-positive macrophages. Having excluded mast cells (positive with mast cell tryptase) and neutrophils (positive with CD15 and Leder stains), there appeared to be a residual population of non-Langerhans cell monocytoid cells (NLMC), which were Mac 387+, CD68-PGM1-, Mast cell tryptase-, CD15-, and CD1a-. Our results showed a predominance of CD8+, TIA-1+ cytotoxic T lymphocytes among the lymphocyte subsets which appear to interact with LC and AM in PLCH lesions. A small sub-population of NLMC was also present. Further studies are required to better define and to evaluate the role of cytotoxic T cells and NLMC in the pathogenesis of PLCH.

ThinPrep Pap tests in patients with endometrial cancer: a histo-cytological correlation.

The aim of this retrospective study was to correlate cytological diagnoses of endometrial cancers in ThinPrep Pap tests with the histological diagnoses. ThinPrep specimens from 67 patients within 12 mo of the histological diagnosis of endometrial cancer were studied. Of this study sample, 89.6% had abnormal Pap tests. Abnormal Pap tests occurred in 96.8, 68.4, and 100% of patients with grades 1, 2, or 3 endometrial cancers, respectively. Of patients with endocervical involvement, 88.9% had positive or suspicious Pap tests, compared with 41.1% without endocervical involvement (LR = 7.85, P < 0.01). Of patients with > or =50% myometrial invasion, 78.9% had positive or suspicious Pap tests, compared with 34.8% with less than 50% invasion (LR = 10.97, P < 0.01). Positive or suspicious Pap tests were found in 59.5 and 32.1% of those with tumors > or =3 cm or <3cm, respectively (LR = 4.85, P < 0.05).

Fulminant multisystem non-langerhans cell histiocytic proliferation with hemophagocytosis: a variant form of Erdheim-Chester disease.

Hemophagocytosis (HP), a feature seen in malignant histiocytosis and infection- and lymphoma-associated disorders, has not been previously emphasized in Erdheim-Chester disease (ECD). Generally, ECD is recognized as a rare, systemic, non-Langerhans cell histiocytosis with a variable clinical course. Herein, we describe a unique case of multisystem non-Langerhans cell histiocytic proliferation with a fulminant clinical course (death occurred within 3 months of presentation) that showed prominent HP and extensive involvement of multiple organs, including the lungs, resulting in respiratory failure. Hemophagocytosis led to severe anemia that required transfusion and thrombocytopenia. Antemortem lung and bone marrow biopsy specimens revealed involvement by a histiocytic infiltrate with features highly suggestive of ECD and HP. Furthermore, the autopsy documented the presence of HP and the histiocytic infiltrate in multiple other organs. This case is best categorized as a variant form of ECD. Recognizing this variant has the following important implications: (1) HP may be a marker for fulminant clinical course in ECD, (2) the presence of HP does not exclude a diagnosis of ECD, and (3) ECD should be considered in the differential diagnosis of HP.

The bronchopulmonary pathology of alpha-1 antitrypsin (AAT) deficiency: findings of the Death Review Committee of the national registry for individuals with Severe Deficiency of Alpha-1 Antitrypsin.

To assess the pathological changes in the lungs and liver of 42 individuals who died while enrolled in the Registry of Individuals with Severe Deficiency of Alpha-1 Antitrypsin (AAT), all available histopathologic surgical or postmortem-derived specimens were reviewed by the pathologist member of the Death Review Committee. The underlying cause of death was emphysema in 34 patients and cirrhosis in 2 patients. Slides of lung were graded for emphysema, and liver specimens were graded for fibrosis, using respective pictorial scoring systems. Correlations between the degree of pathological abnormality and clinical features were evaluated. All lungs exhibited severe panacinar emphysema (mean emphysema score, 7.9 +/- 1.06 [standard deviation], where 10 represents the greatest severity) with a lower lobe predominance. Centriacinar emphysema was minimal. No correlation was found between the pathological severity of emphysema and pulmonary function measurements, and no significant correlation was found between the degree of emphysema and the degree of hepatic fibrosis. Mildly increased bronchial gland-to-wall ratio accompanied mild inflammation and goblet cell hyperplasia. There were minimal changes in small airways. Dilatation of membranous bronchioles was a frequent finding; however, bronchiectasis of larger airways was a minor feature in only 6 patients (15%). Airway morphological features did not correlate with the clinical presence of chronic bronchitis or asthma. Although the lack of correlation between liver and lung pathological changes may reflect different pathogenetic mechanisms of liver disease and lung disease, the lack of correlation between emphysema grade and lung function likely reflects the skewed sample in a series of patients with advanced lung disease.

Germination, viability and clearance of Stachybotrys chartarum in the lungs of infant rats.

Observing that the conidia of Stachybotrys chartarum can germinate in the lung of infant rats, it became important to ascertain whether an infection can ensue. Viable conidia of S. chartarum were instilled into the lungs of 4 and 14 day-old rat pups. Germination was observed frequently in the lungs of 4 day-old but rarely in the 14 day-old pups. In the 4 day-old pups, pulmonary inflammation with hemorrhagic exudates was observed and resulted in about 15% mortality rate compared to 0% for the controls instilled with phosphate buffered saline. Acute neutrophilic inflammation and intense interstitial pneumonia with poorly formed granulomas observed three days following exposure were associated with fungal hyphae and conidia. The surviving experimental pups showed significantly slower weight gain for seven days. Dilution plating and quantitative PCR analysis were used to follow total fungal load in the rat pups lung homogenates. In the 4 day-old rat pups viable fungi decreased rapidly and were less than 1% by day seven. Similarly, fungal DNA decreased exponentially and was only 0.03% by fourteen days after exposure. However, 14 day-old rat pups showed neither the lethal effects of exposures to viable conidia of S. chartarum nor the slower weight gain, and the fungal load decreased even more rapidly. We conclude that S. chartarum conidia can initially germinate and form hyphae but even in the immature rat pups do not establish an effective infection, although a very limited persistence cannot be excluded.

Embolized crospovidone (poly[N-vinyl-2-pyrrolidone]) in the lungs of intravenous drug users.

Crospovidone is an insoluble polymer of N-vinyl-2-pyrrolidone that is used as a disintegrant in pharmaceutical tablets. It can potentially embolize to the lung when aqueous tablet suspensions are injected intravenously. In this report, we identified embolized crospovidone in autopsy-derived lung tissue from three adult IV drug users, 1 man and 2 women, whose ages respectively were 27, 38, and 40 years. Suspected crospovidone was compared with pharmaceutical-grade crospovidone by means of histochemical stains, transmission electron microscopy, and infrared spectroscopy. Similar particles were also observed by light microscopy in a 4-mg tablet of hydromorphone, a preparation prescribed to two of the patients. Two patients had sickle cell disease and were taking methadone and/or hydromorphone for pain management; the third was receiving parenteral hyperalimentation after small bowel resection. Crospovidone appeared as deeply basophilic, coral-like particles within pulmonary arteries and in extravascular foreign-body granulomas. Intrapulmonary crospovidone stained similarly to the pure substance, including intense staining with mucicarmine, Congo red, and Masson trichrome. With Movat pentachrome stain, both intravascular and purified crospovidone appeared orange-yellow, whereas most interstitial particles associated with giant cells stained blue-green. Alcian blue failed to stain intravascular or purified crospovidone but strongly decorated some phagocytized particles. Ultrastructurally, both purified powder and tissue deposits of crospovidone appeared as irregular, electron dense, laminated, and finely granular material. Intrapulmonary crospovidone was associated with inflammatory cells and exhibited degenerative changes. By infrared spectroscopy, crospovidone in tissue had the same spectral characteristics as pharmaceutical grade crospovidone and the library reference, polyvinylpyrrolidone (PVP). We conclude that crospovidone contributes to pulmonary vascular injury in some persons who illicitly inject pharmaceutical tablets. It is readily identifiable histologically and distinguishable from other tablet constituents, such as cornstarch, talc, and microcrystalline cellulose. The variable staining with Alcian blue and Movat suggests that crospovidone is altered in vivo by the inflammatory response.

Infant animal model of pulmonary mycotoxicosis induced by Stachybotrys chartarum.

In recent years cases of often fatal pulmonary hemorrhage in infants have been associated with water damaged homes and the toxigenic fungus Stachybotrys chartarum. The fungal spores contain mycotoxins which could be injurious to the rapidly developing lung. In order to understand the developmental pathophysiology of this disease we developed an infant rat model of stachybotrytoxicosis describing the effects of fungal spores on survival, growth, histopathology of the lung and respiration. Conidia of S. chartarum were instilled intratracheally (1.0-8.0 x 10(5)/gm wt.) in 4-d old Sprague-Dawley rat pups. Two control groups received either sterile PBS or a suspension of spores extensively extracted with ethanol to remove toxins. Lethal dose response was determined (LD50 = 2.7 x 10(5) spores/gm wt.). All dead pups had extensively hemorrhagic lungs. Growth of surviving animals was impaired in a dose-dependent manner. Changes of pulmonary function parameters in rats treated with 1.1 x 10(5) spores/g were consistent with an increased respiratory resistance. Histology of lungs revealed fresh hemorrhage, sparse hemosiderin-laden macrophages, and evidence of inflammation including thickened alveolar septa infiltrated by lymphocytes and mononuclear cells and intra-alveolar macrophages. Significant increases (p = 0.001) in numbers of macrophages (2-fold), lymphocytes (5-fold) and neutrophils (7-fold) were found in BAL fluid. Hemoglobin was elevated 2-fold (p = 0.004). Proinflammatory mediator IL-1beta increased more than 6-fold and TNF-alpha 30-fold (p = 0.001). Extracted spores had a minimal effect on all examined parameters in BAL fluid indicating that mycotoxins are primarily responsible for the hemorrhagic and inflammatory response.