Pleomorphic Adenoma of the Parotid Gland and the Parapharyngeal Space: Two Diametrically Opposing Surgical Philosophies for the Same Histopathologic Entity? †

Background: The aim of this study was to investigate the histopathologic findings in parotid and parapharyngeal pleomorphic adenomas and draw conclusions concerning the surgical strategy. Methods: Retrospective study of medical charts of patients with resected pleomorphic adenomas (PA) between 2005 and 2020 at two tertiary medical referral centers. Histologic specimens were reexamined by an experienced head and neck pathologist. Patients with insufficient/incomplete data were excluded from our study sample. Results: A total of 844 patients formed our study sample (291 men, 553 women, average age 48.9 years); 786 cases had a PA in the parotid gland (PG) (93.1%), and the remaining 58 cases had a PA in the parapharyngeal space (PS) (6.9%). Recurrences were detected in 8/844 cases (7/786 in the PG, 1/58 in the PS, 0.94% in total) with a mean follow-up time of 86.7 months (10–189 months) with no statistically significant differences between the study groups (p = 0.527). Our analysis showed that parapharyngeal pleomorphic adenomas are characterized by a lower incidence of an intact anatomical capsule (71.4% vs. 82.6%, p = 0.035) and a remarkably more frequent occurrence of satellite nodules (20.7% vs. 7.5%, p < 0.001). Conclusions: The more challenging histopathologic profile of parapharyngeal pleomorphic adenomas points towards the fact that parapharyngeal surgery should remain in the hands of experienced surgeons at high-volume centers.

Beyond Bronchiolitis Obliterans: In-Depth Histopathologic Characterization of Bronchiolitis Obliterans Syndrome after Lung Transplantation

Bronchiolitis obliterans syndrome (BOS) is considered an airway-centered disease, with bronchiolitis obliterans (BO) as pathologic hallmark. However, the histologic spectrum of pure clinical BOS remains poorly characterized. We provide the first in-depth histopathologic description of well-characterized BOS patients and patients without chronic lung allograft dysfunction (CLAD), defined according to the recent consensus guidelines. Explant lung tissue from 52 clinically-defined BOS and 26 non-CLAD patients (collected 1993–2018) was analyzed for histologic parameters, including but not limited to airway lesions, vasculopathy and fibrosis. In BOS, BO lesions were evident in 38 (73%) patients and varied from concentric sub-epithelial fibrotic BO to inflammatory BO, while 10/14 patients without BO displayed ‘vanishing airways’, defined by a discordance between arteries and airways. Chronic vascular abnormalities were detected in 22 (42%) patients. Ashcroft fibrosis scores revealed a median of 43% (IQR: 23–69) of normal lung parenchyma per patient; 26% (IQR: 18–37) of minimal alveolar fibrous thickening; and 11% (IQR: 4–18) of moderate alveolar thickening without architectural damage. Patchy areas of definite fibrotic damage to the lung structure (i.e., Ashcroft score ≥ 5) were present in 28 (54%) patients. Fibrosis was classified as bronchocentric (n = 21/28, 75%), paraseptal (n = 17/28, 61%) and subpleural (n = 15/28, 54%). In non-CLAD patients, BO lesions were absent, chronic vascular abnormalities present in 1 (4%) patient and mean Ashcroft scores were significantly lower compared to BOS (p = 0.0038) with 78% (IQR:64–88) normally preserved lung parenchyma. BOS explant lungs revealed evidence of various histopathologic findings, including vasculopathy and fibrotic changes, which may contribute to the pathophysiology of BOS.

Ocular findings in cats with blastomycosis: 19 cases (1978–2019)

OBJECTIVE To document ocular findings in cats with blastomycosis. ANIMALS 35 cats with blastomycosis. PROCEDURES Medical records from 1978 through 2019 were reviewed to identify cats with confirmed Blastomyces infection. Cats were grouped as having or not having ocular involvement. Clinical signs, histopathologic findings, and response to treatment were evaluated. RESULTS 21 of the 35 (60%) cats with confirmed blastomycosis had ocular abnormalities. Two of 21 cats with ocular abnormalities also had systemic hypertension and were excluded. Of the remaining 19 cats, 15 (79%) had bilateral ocular signs. Ten (53%) cats had inflammatory ocular lesions, and 9 (47%) had neuro-ophthalmic abnormalities. Six of the 19 (32%) cats appeared to be completely blind, and 5 (26%) appeared to be unilaterally blind. For the 10 cats with inflammatory ocular lesions, the most common lesions were anterior uveitis (9/20 eyes), active chorioretinitis (6/20 eyes), and retinal detachment (4/20 eyes). For the 9 cats with neuro-ophthalmic abnormalities, the most common abnormalities were a negative menace or tracking response (10/18 eyes) and negative pupillary light response (4/18 eyes). CLINICAL RELEVANCE Results suggested that ocular involvement is common in cats with blastomycosis and that both inflammatory lesions and neuro-ophthalmic abnormalities can be seen. Blastomycosis should be considered in the differential diagnosis for cats with anterior uveitis, posterior segment inflammation, or neuro-ophthalmic abnormalities, and a complete ophthalmic examination should be performed in all cats with confirmed or suspected blastomycosis.

Intermittent Fasting before Laparotomy: Effects on Glucose Control and Histopathologic Findings in Diabetic Rats

(1) Background: Intermittent fasting is a nutrition practice in which individuals fast for several hours in a day, mainly with feeding time during the daylight hours. They seek to improve metabolic performance and cellular resistance to stress. In this study, we tested the fasting protocol to investigate the glycemic effect in a laparotomy perioperative period in diabetic rats and histopathologic findings. (2) Methods: The animals were diabetic-induced with alloxan. Two groups were set according to the feeding protocol: free food and intermittent fasting, whose rats could only eat 8 h in the daylight. Both groups were anesthetized, and a laparotomy was performed. We evaluated the glucose levels during the perioperative period, and we accessed organ histology seeking damage of kidney, bowel and liver after surgical trauma, and we evaluated the wound healing process. (3) Results: Glycemic levels were improved in the intermittent fasting group, especially in the post-operative period after laparotomy. Comparing both groups’ tubular damage showed interdependency with mice with worse glycemic level (Z = 2.3; p = 0.0215) and wound-healing parameters showed interdependency with rats with better glycemic status for neovascularization (Z = 2.2; p = 0.0273) and the presence of sebaceous and sweat gland in the healing process (Z = 2.30; p = 0.0215). (4) Conclusions: Intermittent fasting before surgery can be a tool to improve glycemic levels in diabetic rats, with improvement especially in the post-operative period.

Premature death in dogs with nontraumatic hemoabdomen and splenectomy with benign histopathologic findings

OBJECTIVE To determine whether premature death occurred among dogs with nonmalignant splenic histopathologic findings after splenectomy for nontraumatic hemoabdomen. ANIMALS 197 dogs with nontraumatic hemoabdomen that underwent splenectomy and histopathologic evaluation between 2005 and 2018. PROCEDURES Information was obtained from electronic medical records, dog owners, and referring veterinarians to determine patient characteristics, histopathologic findings, survival information, and cause of death. Dogs were grouped based on histopathological diagnosis and outcome, and median survival times (MSTs) and risk factors for death were determined. RESULTS Histopathologic findings indicated malignancy in 144 of the 197 (73.1%) dogs with nontraumatic hemoabdomen. Hemangiosarcoma was diagnosed in 126 dogs (87.5% of those with malignancies and 64.0% of all dogs). Nine of 53 (17%) dogs with nonmalignant histopathologic findings had an adverse outcome and premature death, with an MST of 49 days. Risk factors for this outcome included low plasma total solids concentration, an elevated hemangiosarcoma likelihood prediction score, and a medium or high hemangiosarcoma likelihood prediction score category. CONCLUSIONS AND CLINICAL RELEVANCE This study showed that there is a group of dogs with nontraumatic hemoabdomen due to splenic disease that have nonmalignant histopathologic findings after splenectomy, but nonetheless suffer an adverse outcome and die prematurely of a suspected malignancy. Further evaluation of potential at-risk populations may yield detection of otherwise overlooked malignancies.

Bronchial brush cytology, endobronchial biopsy, and SALSA immunohistochemistry in severe equine asthma

Horses with severe equine asthma (SEA), also known as heaves and recurrent airway obstruction, have persistent neutrophilic inflammation of the lower airways. Cytologic evaluation of bronchoalveolar lavage (BAL) fluid is commonly used to confirm the clinical diagnosis of SEA. However, the utility of microscopic assessment of bronchial brushings, endobronchial biopsies, and immunohistochemical detection of disease-associated biomarkers for the diagnosis of SEA remain poorly characterized. Salivary scavenger and agglutinin (SALSA) has anti-inflammatory properties and downregulated gene expression in SEA; therefore, it was investigated as a tissue biomarker for airway and systemic inflammation. Six asthmatic and 6 non-asthmatic horses were exposed to an inhaled challenge. Before and after challenge, samples of BAL fluid, bronchial brushing, and endobronchial biopsy were collected. Location of SALSA in biopsies was determined, and immunohistochemical label intensity was computed using image analysis software. Serum amyloid A (SAA) was measured to assess systemic inflammation. After challenge, neutrophil proportions were significantly higher in asthmatic versus non-asthmatic horses in BAL fluid (least squares means, 95% confidence interval: 80.9%, 57.2% to 93.1%, vs 3.6%, 1.1% to 10.7%) and in brush cytology slides (39.5%, 7.7% to 83.6%, vs 0.2%, 0% to 2.3%), illustrating the potential of brush cytology as an alternate modality to BAL for assessing intraluminal inflammation. Bronchial histopathologic findings and intensity of SALSA immunolabeling in surface and glandular epithelium were similar in asthmatic and non-asthmatic horses, indicating limited changes in bronchial tissue from the inhaled challenge. Increases in SAA indicated systemic inflammation, but SALSA immunolabeling did not change significantly.

Histopathologic Findings Associated With Matrix Metalloproteinases Proceeding to Recurrence of Primary Spontaneous Pneumothorax in Adolescents

Background: Primary spontaneous pneumothorax is potentially life-threatening, and its recurrence is always a serious problem. Pathological examination provides molecular insights into the pathophysiology of primary spontaneous pneumothorax.Objectives: To investigate the association of histopathologic features of primary spontaneous pneumothorax with matrix metalloproteinase expression and their relevance to the recurrence.Methods: A total of 217 tissue section slides in 172 adolescent patients with primary spontaneous pneumothorax were retrospectively reviewed from January 2001 to June 2020. All histopathologic features were recorded and pathologic findings related to ipsilateral recurrence and second surgery were analyzed. Serum levels of matrix metalloproteinases were prospectively measured in 25 primary spontaneous pneumothorax patients receiving surgery and 18 healthy controls. Their relevance to the histopathologic features of primary spontaneous pneumothorax related to its recurrence was also examined.Results: The major presenting histopathologic findings of primary spontaneous pneumothorax were bleb/bulla (98%) followed by fibrosis (68%). Low prevalence of the pathologic findings of granulation tissue and macrophage accumulation were significantly associated with recurrent primary spontaneous pneumothorax, whereas fibrosis was significantly higher in patients receiving more than once surgery. Furthermore, the ratios of matrix metalloproteinase-2/tissue inhibitor of metalloproteinase-1 and matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 were significantly higher in theses pathological findings as well as multinucleated giant cells and mesothelial cell hyperplasia in comparison with healthy controls.Conclusions: Low prevalence of macrophage accumulation and granulation tissue related to the overexpression of matrix metalloproteinase-2 and−9 activities may contribute to healing impairment and primary spontaneous pneumothorax recurrence.

The Effect of Insect Repellent Exposure on Leukocyte Profile and Histopathologic Findings in Lungs

Organophosphate compounds in insect repellent have a role in contributing to mosquito mortality but have toxic effects for humans when exposed for a long time. The research is aimed to analyze the effect of insect repellent exposure in blood leukocyte profile and histopathologic findings in lungs. The study used thirty males Rattus novergicus, which were divided into three groups, such as electric liquid insect repellent (P1) with contain 0.031% dimefluthrin, anti-mosquito coils (P2) with 0.014% dimefluthrin, and electric mat mosquito repellent with 0.566% dimefluthrin for 8 hours in 20 days respectively. Leukocyte profiles were determined by using the blood smear method, and the lung’s health was identified by histopathologic findings. Based on the results study showed mosquito coils exposure increase the lymphocytes count. Meanwhile, the electric liquid-repellent increased the basophil’s numbers. The electric mat exposure had more eosinophils, neutrophils stab, neutrophils segment, and monocytes in the blood. The leukocyte profile of each group showed there were no statistically significant differences (P-value > 0.05). Based on histopathology, lung findings showed that the electric mat exposure contributed to cells degeneration 7.5% and pleural thickening 30%. The higher dimefluthrin concentrations in insect repellents could affect leukocyte profile and lungs health.