Patient: Chief Complaint: Family history: Social history: History of Present Illness: Physical Examination Results:

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1 Uncontrolled Pneumonia in a 49-Year-Old White Man Farnoush Taghizadeh, BS, MLS(ASCP),1* Raghuraj S Raghuwanshi M, MD Lab Med Summer 2014;45:e123-e127 DOI: /LMeq9ie7aqqpgdgdoy Clinical History Patient: A 49-year-old white man. Chief Complaint: Shortness of breath, fever, and ongoing unintended weight loss. History of Present Illness: The patient had arrived at the emergency department of a hospital in St. Augustine, Florida with coughing and progressive shortness of breath. He reported that he had been experiencing these symptoms for the past 6 weeks. He was examined by his primary physician, who had prescribed him a course of antibiotics and treated him on an outpatient basis. The patient reported no improvement in his symptoms at present, despite the antibiotics. He mentioned that he had traveled to St. Augustine, Florida approximately 10 days previously. Medical personnel in the emergency department subsequently performed a chest x-ray on the patient, as well as computed tomography (CT) scanning of his lymphadenopathy. Medical and Family History: Positive for hypertension, diabetes Abbreviations: ALT, aminotransferase; AST, aspartate aminotransferase; GMS, Grocott-Gömöri methenamine silver stain; PAS, periodic acid Schiff; TNF-α, tumor necrosis factor alpha; TGF-β, transforming growth factor beta; BUN, blood urea nitrogen; RBCs, red blood cells; NA, not applicable; WBC, white blood cell; LPF, low power field; GPCs, Gram positive cocci; GPRs, Gram positive rods 1 Biology Department, University of North Florida, Jacksonville, FL 2 Pathology Department, Flagler Hospital, St. Augustine, FL *To whom correspondence should be addressed: fortaghizadeh@gmail.com mellitus, and osteoporosis. He reported that he has chewed 2 packs of chewing tobacco per day for the past 30 years, occasionally drinks alcohol, and is a nonsmoker with no known allergies. Family history: Noncontributory. Social history: Noncontributory. Physical Examination Results: The patient exhibited mild respiratory distress; however, he was awake, alert, and oriented, with a temperature of 37.3 C. He also exhibited poor respiratory effort with diffuse expiratory rhonchi. His heart rate and heart rhythm were regular, with no murmurs, gallops, or rubs. His bowel sounds were positive; he exhibited no organomegaly and no cyanosis, clubbing, or edema of his extremities. Laboratory Findings: Table 1; Table 2; Image 1. Keywords: fungal infection, blastomycosis, metaplastic cells, liposomal amphotericin B, broad base budding yeast, BAD 1 (adhesion protein) Questions 1. What are the most striking clinical and laboratory findings for the patient? 2. What type of organisms other than bacteria might cause the symptoms that the patient experienced? 3. What is the diagnosis for the patient? 4. How did this patient contract this infection? 5. What are some treatment regimens available for this patient? Answers 1. The striking clinical findings of the patient are abnormal results on chest x-ray imaging, the presence of 2+ yeast in his sputum, no bacterial pathogens isolated from his sputum, unintentional weight loss, fever, and diabetes mellitus (Table 1). Also significant is the fact that he is Summer 2014 Volume 45, Number 3 Lab Medicine e123

2 Table 1. Initial Microbiological Findings a Variable Sputum screen Sputum gram staining Sputum culture Blood culture Urine culture Result 25 WBCs/LPF 10 epithelial cells/lpf Moderate amount of WBCs Moderate amount of epithelial cells Few GPCs Few GPRs Moderate yeast 2+ yeast not Cryptococcus genus Negative results for presence of bacteria Negative results for presence of bacteria WBC, white blood cell; LPF, low-power field; GPCs, Gram positive cocci; GPRs, Gram positive rods. a Patient is a 49-year-old white man. Table 2. Initial Biochemical Findings a Test Result Reference Value Glucose 256 mg/dl mg/dl BUN 20 mg/dl 7-23 mg/dl Creatinine 0.9 mg/dl mg/dl Sodium 134 meq/l meq/l Potassium 4.2 meq/l meq/l Chloride 90 meq/l meq/l CO 2 33 meq/l meq/l Anion gap 10.5 meq/l meq/l Calcium 8.7 mg/dl mg/dl Total protein 5.8 g/dl g/dl Albumin 2.8 g/dl g/dl Bilirubin, total 0.3 mg/dl mg/dl AST 77 U/L U/L ALT 73 U/L U/L Lactic acid 2.60 mmol/l mmol/l BUN, blood urea nitrogen; AST, aspartame transaminase; ALT, alkaline transaminase. a Patient is a 49-year-old white man. from Missouri, a region in which certain fungi are endemic. All of these results indicate that further testing is required to identify the kind of pathogenic organism that is causing infection in the patient. 1 The mildly elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels that he experienced (Table 2) are frequently found in patients with diabetes mellitus; also, decrease in total protein and albumin levels can be associated with malnutrition. Chest radiographic imaging of our patient (portable view of the chest) demonstrated opacity in the right upper lung lobe, right lower lobe, and left lower lobes, respectively. These findings most likely represent multifocal pneumonia. Increase in CO 2 levels often occurs due to lung infiltration and inadequate expansion of the lung (Table 2). At this point the direct microscopic characteristics of 2+ yeast-like cells are significant, so we suspect fungal infection. The increase in neutrophil count and decrease in lymphocyte count that we observed in our patient are usually a response to infection. Therefore, we performed more tests, such as bronchial wash followed by correlation with culture. Bronchial wash results showing atypical metaplastic cells and reactive epithelial bronchial cells are usually accompanied by fungal infection. 2. The bronchial smear results showing a large (10-15 µm) single budding yeast cell, with a thick and refractile cell wall, are indicative of Blastomycosis dermatitidis). For definitive identification, additional testing will be required. 3. Lactophenol cotton blue preparation of cultured lung tissue showed single smooth-walled, round to oval conidia at the end of short condiophores that are located on the hyphae. Histological examination of Grocott- Gömöri methenamine silver stain (GMS) and periodic acid Schiff (PAS) stain results showed round, budding yeast and lack of mucicarminophilic capsule. The overall size and appearance of the morphologic characteristics of these organisms are most consistent with blastomycosis (Image 1). Therefore, the cause of acute fungal pneumonia in our patient was Blastomycosis dermatitidis. 4. The patient has lived his entire life in Missouri, an area in which Blastomycosis dermatitidis is endemic. He probably became infected during one of his outdoor activities by inhaling the conidia of that fungus. Also, because he was immunosuppressed due to his diabetes mellitus, his body was not able to resolve the infection; therefore, he developed severe acute pulmonary fungal pneumonia. 5. According to the Clinical Practice Guideline for the Management of Blastomycosis: 2008 Update by the Infectious Diseases Society of America, 2 moderate to severe pulmonary infection with or without dissemination needs to be treated with lipid amphotericin B, 3 to 5 mg per kg body weight per day, or deoxycholate amphotericin B, 0.7 to 1 mg per kg body weight per day, for 1 to 2 weeks. This regimen should then be followed with itraconazole, 200 mg twice daily for 6 to 12 e124 Lab Medicine Summer 2014 Volume 45, Number 3

3 A B Image 1 Staining of specimen material from our patient, a 49-year-old white man. A, Periodic acid Schiff stain (PAS) results (magnification 10). B, Grocott-Gömöri methenamine silver stain (GMS) results (magnification 10) demonstrating broad-budding yeast, the morphologic characteristics of which are consistent with Blastomycosis dermatitidis. months. Discussion Blastomycosis is a systemic fungal infection caused by Blastomycosis dermatitis, which is the asexual phase of this fungus, as in Ajellomyces dermatitis. 3 B. dermatitis is a dimorphic fungus. To grow B. dermatitis in the mold phase, the laboratory scientist must plate it on Sabouraud dextrose agar at 25 C for 2 to 3 weeks. The mold phase appears as white, cottony mycelium on the surface, and the reverse is brownish. Microscopic examination of mold phase reveals single smooth-walled, round-to-oval conidia at the end of short conidiphores or directly on the hyphae. The mycelial growth is converted to yeast form by incubation at 37 C. Microscopic examination of the yeast phase reveals a large, round, thick-walled, single budding yeast with a wide base. The cells are 10 µm to 15 µm in diameter; this wide base is one of the most widely recognizable characteristics of B. dermatitis. Epidemiology Blastomycosis, also known as North American blastomycosis, 4 Gilchrist disease, and Chicago disease, is endemic to the regions of the United States that are adjacent to the Mississippi and Ohio River Valleys (Missouri, Kentucky, Arkansas, Mississippi, North Carolina, Tennessee, Louisiana, Illinois, and Wisconsin). The condition also has been reported in the United Kingdom, Canada, Africa, India, and the Middle East. Outbreaks are associated with outdoor occupational and recreational activity. Also, blastomycosis is more common in men than in women and children. This is simply because men tend to be more involved in outdoor activities, especially along rivers and streams, where they are exposed to moist soil containing rich organic matter. Virulence Factor An adherence factor called Blastomyces adhesion (BAD1) only exists in the yeast phase. 4 The immunoreactive protein antigen BAD1 binds to chitin on the yeast-cell wall. This surface molecule works as a type of adhesion and virulence factor that bind the fungus to complement Summer 2014 Volume 45, Number 3 Lab Medicine e125

4 3 receptors and CD14 on macrophages and lung tissue. BAD1 also alters the phagocytes by decreasing the production of tumor necrosis factor alpha (TNF-α in phagocytes and increasing the production of the transforming growth factor beta (TGF-β, which aids in the progression of pulmonary infections). BAD1 is also responsible for creating a calcium-poor environment that enables yeast to grow. 5 Melanin production is another virulence factor that protects the yeast from oxidative reaction of leukocytes. Pathogenicity Infection begins by inhalation of conidia from the mold phase into the lungs. 3 Primary pulmonary infection starts when organisms start to become phagocytes by means of the bronchopulmonary mononuclear cells. The extrapulmonary infection occurs due to dissemination of primary pulmonary infection by the bloodstream and the lymphatic system. The inflammatory response includes accumulation of polymorphonuclear leukocytes with noncaseous granulomas with epithelial and giant cells. Clinical Presentations Pulmonary Infection Acute pneumonia After the inhalation of the conidia into the lung(s), primary lesions appear. 3 At this point, the pneumonia is a clinical symptom of blastomycosis and resembles such other conditions as tuberculosis and histoplasma. Many patients with acute pneumonia are initially asymptomatic but experience sudden onset of myalgia, fever, chills, transient pleuritic chest pain, and nonproductive coughing. Chest x-ray imaging shows infiltration in lower lobes. At this point, the infection typically resolves by itself. The fungus can spread and cause disintegration of skin and osseous structures. Chronic infection In this type of infection, the primary infection does not heal, which results in chronic pneumonia with productive cough, hemoptysis, unintended weight loss, pleuritic chest pain, low-grade fever, and respiratory failure. 3 The chest x-ray imaging shows upper lobe infiltration. Extrapulmonary Infection Extrapulmonary infection occurs when the primary infection spreads to other regions of the body. 3 Symptoms include infections of the skin, bones and joints, genitourinary tract, and central nervous system. Diagnosis Direct Microscopy Specimen material from infected areas of the body, such as the lungs and skin, along with sputum and cerebrospinal fluid, should be examined. The laboratory scientist should look for large, single, budding yeast with a wide base and a double-wall counter. Histopathology Specimen material obtained via biopsy or aspiration can be stained with periodic acid Schiff (PAS) and Grocott-Gömöri methenamine silver (GMS) to visualize the blastomycosis. 6 The tissue specimen can also be subjected to hematoxylin-eosin staining to visualize the inflammatory response to the infection. These useful tools can help the laboratory scientist to distinguish the differential diagnoses of Paracoccidioides brasiliensis, Histoplasma capsulatum, and Coccidioides immitis. Culture Culture is an extremely useful tool for identifying blastomycosis; however, growth is not always possible. Also, it can take at least 10 to 15 days to observe any growth. 7 Positive culture results confirm the presence of the condition in question. The colonies (if present) have a whitish, smooth, hairy appearance. Serologic Testing Antibody detection is available but it has low sensibility and specificity. 7 However, antigen detection in certain bodily fluids, such as urine, has sensitivity of greater than 90%. DNA Probe A DNA probe, such as Gen-Probe (Gen-Probe Inc., San Diego, CA) allows a rapid identification of blastomycosis from culture. 7 This method uses nucleic acid hybridization to isolate Blastomycosis dermatitis e126 Lab Medicine Summer 2014 Volume 45, Number 3

5 from culture. Treatment Treatment is different based on the severity and type of blastomycosis infection. Patients with mild to moderate illness are treated with itraconazole for 6 to 12 months. Patients with severe illness are treated with amphotericin B until they experience improved health; at that point, they follow a regimen of oral itraconazole for an additional 6 to 12 months. 8 Because amphotericin B has a high degree of toxicity, liposomes amphotericin B is a stronger choice. References 1. Meltzer A, Everhart JE. Associations between diabetes and elevated serum alanine aminotransferase activity among Mexican Americans. Am J Epidemiol. 1997;146(7): Chapman SW. Clinical Practice guideline for the management of blastomycosis: 2008 updates by the Infectious Diseases Society of America. Clin Infect Dis. 2008;46(12): Saccente M, Woods GL. Clinical and laboratory updates on blastomycosis. Clin Microbiol Rev. 2010;23(2): López-Martínez R, Méndéz-Tovar LJ. Blastomycosis. Clin Dermatol. 2012;30: Brandhorset TT, Gauthier GM, Stein RA, Kline BS. Calcium binding by the essential virulence factor BAD-1 of Blastomyces dermatitidis. J Biol Chem. 2005;280: Guarner J, Brandt ME. Histopathologic of fungal infection in the 21 st century. Clin Microbiol Rev. 2011;24(2): Smith JA, Kauffman CA. Pulmonary fungal infections. Respirology. 2012;17: Ariano, Robert E, Mitchelmore BR, Lagacé-Wiens PR, Zelenitsky SA. Successful treatment of pulmonary blastomycosis with continuously infused amphotericin B deoxycholate after failure with liposomal amphotericin B. Ann Pharmacother. 2013;47(6): e26. doi: / aph.1r703. Summer 2014 Volume 45, Number 3 Lab Medicine e127