PCCSOM 2026 Microbiology F.04 Opportunistic Mycoses PDF

PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES MICROBIOLOGY LECTURE LECTURER: ARLENE L. QUITASOL, MD, FPSP DATE: MAY 13,2024 TOPIC OUTLINE Opportunistic Mycoses A. Candidiasis B. Cryptococcosis C. Aspergillosis D. Mucormycosis (Zygomycosis) E. Pneumocystis pneumonia F. Penicilliosis OPPORTUNIS...

PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES MICROBIOLOGY LECTURE LECTURER: ARLENE L. QUITASOL, MD, FPSP DATE: MAY 13,2024 TOPIC OUTLINE Opportunistic Mycoses A. Candidiasis B. Cryptococcosis C. Aspergillosis D. Mucormycosis (Zygomycosis) E. Pneumocystis pneumonia F. Penicilliosis OPPORTUNISTIC MYCOSES Patients with compromised host defenses are susceptible to ubiquitous fungi to which healthy people are exposed but usually resistant Include: o Candidiasis o Cryptococcosis o Aspergillosis o Mucormycosis o Pneumocystis pneumonia o Penicilliosis CANDIDIASIS Caused by yeast genus Candida o Members of the normal flora: ▪ Skin ▪ Mucous membranes ▪ Gastrointestinal tract o Colonize the mucosal surfaces of all humans soon after birth o Risk of endogenous infection is ever present Most prevalent systemic mycosis Most common agents are: o Candida albicans o Candida parapsilosis o Candida glabrata o Candida tropicalis o Candida guilliermondii o Candida dubliniensis Widespread use of fluconazole has precipitated the emergence of more azole-resistant species: o Candida glabrata o Candida krusei o Candida lusitaniae Candida auris: Global emergence of a multidrug-resistant species They also form pseudohyphae when the buds continue to grow but fail to detach, producing chains of elongated cells that are pinched or constricted at the septations between cells Unlike other species of Candida, C. albicans is dimorphic; in addition to yeasts and pseudohyphae, it can also produce true hyphae Candida albicans. Budding yeast cells (blastoconidia), hyphae, and pseudohyphae. 400×. On agar media or within 24 hours at 37°C or room temperature, o Candida species produce soft, cream-colored colonies with a yeasty odor Two simple morphologic tests distinguish C. albicans from other species of Candida: o After incubation in serum for about 90 minutes at 37°C, yeast cells of C. albicans will begin to form true hyphae or germ tubes o On nutritionally deficient media, C. albicans produces large, spherical chlamydospores. Germ tube. Unlike other species of Candida, Candida albicans produces true hyphae as well as budding yeast cells and pseudohyphae. After incubation in serum at 37°C for 60–90 minutes in the laboratory, clinical isolates of Candida albicans are stimulated to form hyphae, and this process is initiated by the production of germ tubes, which are thinner and more uniform than pseudohyphae. 1000×. Characteristics morphology of Candida albicans MORPHOLOGY AND IDENTIFICATION In culture or tissue, Candida species grow as oval, budding yeast cells (3–6 μm in size) Pseudohyphae NOTE TAKER: BALDOS | FERRER | PADAYAO Page 1 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES Once in the circulation: o Infect the kidneys o Attach to prosthetic heart valves o Produce candidal infections almost anywhere (eg, arthritis, meningitis, and endophthalmitis) Critical host defense against systemic candidiasis is an adequate number of functional neutrophils capable of ingesting and killing the yeast cells Yeast Hyphae SUGAR FERMENTATION and ASSIMILATION TESTS - can be used to confirm the identification and speciate the more common Candida isolates, such as C. tropicalis, C. parapsilosis, C. guilliermondii, Candida kefyr, C. krusei, and C. lusitaniae. Candida glabrata - Unique among these pathogens because on routine culture media it produces only yeast cells and no pseudohyphae PATHOGENESIS AND PATHOLOGY A. CUTANEOUS OR MUCOCUTANEOUS CANDIDIASIS Increase in the local number of Candida and damage to the skin or epithelium that permits local invasion by the yeasts and pseudohyphae Characterized by inflammatory reactions varying from pyogenic abscesses to chronic granulomas Lesions contain abundant budding yeast cells and pseudohyphae Administration of broad-spectrum antibiotics often promotes large increases in the endogenous population of Candida in the gastrointestinal tract, oral and vaginal mucosa B. SYSTEMIC CANDIDIASIS Occurs when Candida enters the bloodstream and the innate phagocytic host defenses are inadequate to contain the growth and dissemination of the yeasts Yeasts can enter the circulation by crossing the intestinal mucosa Many nosocomial cases are caused by contamination of indwelling intravenous catheters with Candida NOTE TAKER: BALDOS | FERRER | PADAYAO CLINICAL FINDINGS A. Cutaneous and Mucosal Candidiasis Risk factors associated with superficial candidiasis include: o AIDS o Pregnancy o Diabetes o Young or old age o Trauma (burns, maceration of the skin) THRUSH o Occur on the tongue, lips, gums, or palate o Patchy to confluent, whitish pseudomembranous lesion composed of epithelial cells, yeasts, and pseudohyphae, which can lead to the formation of an intractable biofilm ORAL THRUSH VULVOVAGINITIS o Yeast invasion of the vaginal mucosa characterized by irritation, pruritus, and vaginal discharge o Often predisposed by conditions, such as diabetes, pregnancy, or antibacterial drugs that alter the microbiota, local acidity, or secretions. OTHER FORMS OF CUTANEOUS CANDIDIASIS: o Intertriginous infection occurs in moist, warm parts of the body such as the axillae, groin, and intergluteal or inframammary folds ▪ Most common in obese and diabetic individuals o Before newborns establish a balanced microbiome, they are susceptible to extensive diaper rash and skin infection caused by Candida ▪ Infected areas become red and moist and may develop vesicles Page 2 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES o Interdigital involvement between the fingers follows repeated prolonged immersion in water ▪ Most common in homemakers, bartenders, cooks, and vegetable and fish handlers o ONYCHOMYCOSIS ▪ Caused by Candidal invasion of the nails and around the nail plate ▪ Painful, erythematous swelling of the nail fold resembling a pyogenic paronychia, which may eventually destroy the nail B. Systemic Candidiasis Candidemia can be caused by: o Indwelling catheters o Surgery o Intravenous drug abuse o Aspiration o Damage to the skin or gastrointestinal tract Patients with normal innate immune responses and circulating neutrophils: o The yeasts are eliminated o Candidemia is transient Patients with compromised innate phagocytic defenses o May develop occult lesions anywhere, especially the kidney, skin (maculonodular lesions), eye, heart, and meninges Most often associated with: o Chronic administration of corticosteroids or other immunosuppressive agents o Hematologic diseases such as leukemia, lymphoma, and aplastic anemia o Chronic granulomatous disease Candidal endocarditis o Frequently preceded by the deposition and growth of the yeasts and pseudohyphae on prosthetic heart valves or vegetations Kidney infections Urinary tract infections are often associated with: o Foley catheters o Diabetes o Pregnancy o Antibacterial antibiotics C. Chronic Mucocutaneous Candidiasis Rare but distinctive clinical manifestation Characterized by the formation of granulomatous candidal lesions on any or all cutaneous and/or mucosal surfaces Most common forms present in early childhood and are associated with autoimmunity and hypoparathyroidism Chronic, raised, and crusty highly disfiguring keratitic lesions on the skin, oral mucosa, and scalp NOTE TAKER: BALDOS | FERRER | PADAYAO Many patients with chronic mucocutaneous candidiasis are unable to mount an effective Th17 response to Candida DIAGNOSTIC LABORATORY TESTS A. Specimens and Microscopic Examination Specimens include: o Swabs and scrapings from superficial lesions o Blood o CSF o Tissue biopsies o Urine o Exudates o Material from removed intravenous catheters B. Culture Yeast colonies are examined for the presence of pseudohyphae C. albicans is identified by the production of germ tubes or chlamydospores Other yeast isolates are speciated phenotypically by using any of several commercial kits to test for the metabolic assimilation of a battery of organic substrates Candidiasis. Yeasts and pseudohyphae in tissue, stained with periodic acid-Schiff. 1000×. Page 3 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES CHROMagar® o Useful commercial medium for the rapid identification of several Candida species based on fungal enzymatic action on chromogenic substrates in the medium o After incubation for 1–4 days on CHROMagar ▪ C. albicans - green ▪ C. tropicalis - blue ▪ C. glabrata - dark purple ▪ C. parapsilosis, C. lusitaniae, C. guilliermondii, and C. krusei - pinkish hue Any positive culture from normally sterile body sites is significant Positive blood cultures may reflect systemic candidiasis or transient candidemia due to a contaminated intravenous line Cultures of skin lesions are confirmatory and distinguish cutaneous candidiasis from dermatophytosis TREATMENT Thrush and other mucocutaneous forms of candidiasis o Topical nystatin or oral ketoconazole or fluconazole Clearing of cutaneous lesions is accelerated by eliminating contributing factors such as excessive moisture or antibacterial drugs Systemic candidiasis o Treated with amphotericin B, sometimes in conjunction with oral flucytosine, fluconazole, or caspofungin Chronic mucocutaneous candidiasis o Oral ketoconazole and other azoles o Patients with genetic cellular immune defect often require lifelong treatment EPIDEMIOLOGY AND CONTROL Most important preventive measure is to avoid disturbing the normal balance of microbiota and intact host defenses Candidiasis is not communicable, since virtually all persons normally harbor the organism NOTE TAKER: BALDOS | FERRER | PADAYAO CRYPTOCOCCOSIS Cryptococcus neoformans and Cryptococcus gattii o Environmental, basidiomycetous yeasts o Yeast cells possess large polysaccharide capsules Cryptococcus neoformans o Occurs worldwide in nature and is isolated readily from dry pigeon feces, as well as trees, soil, and other sites o occurs in immunocompetent persons but more often in patients with HIV/AIDS Cryptococcus gattii o Less common and typically associated with trees in tropical areas Both species cause cryptococcosis, which follows inhalation of desiccated yeast cells or possibly the smaller basidiospores From the lungs, these neurotropic yeasts typically migrate to the central nervous system where they cause meningoencephalitis Have the capacity to infect many other organs (eg, skin, eyes, and prostate) MORPHOLOGY AND IDENTIFICATION In culture, Cryptococcus species produce whitish mucoid colonies within 2– 3 days Microscopically, in culture or clinical material, o Spherical budding yeast cells (5–10 μm in diameter) are surrounded by a thick non-staining capsule o All species of Cryptococcus, including several nonpathogenic species, are encapsulated and possess urease C. neoformans and C. gattii differ from nonpathogenic species by: o Abilities to grow at 37°C o Production of LACCASE ▪ a phenol oxidase, which catalyzes the formation of melanin from appropriate phenolic substrates (eg, catecholamines). Both the capsule and laccase are well-characterized virulence factors. Cryptococcosis. The capsule of Cryptococcus neoformans is notably apparent in this pulmonary lavage specimen. Giemsa’s stain. 1000×. Page 4 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES PATHOGENESIS Infection is initiated by inhalation of the yeast cells Primary pulmonary infection may be asymptomatic or may mimic an influenza-like respiratory infection, often resolving spontaneously In patients who are compromised, o Yeasts may multiply and disseminate to other parts of the body but preferentially to the central nervous system, causing cryptococcal meningoencephalitis o Inflammatory reaction is usually minimal or granulomatous Other common sites of dissemination include: o Skin o Adrenals o Bone o Eye o Prostate gland CLINICAL FINDINGS Major clinical manifestation: CHRONIC MENINGITIS Cerebrospinal fluid pressure, protein concentration, and cell count may be elevated, whereas the glucose is normal or low Patients may complain of headache, neck stiffness, and disorientation. In addition, there may be lesions in skin, lungs, or other organs Untreated cases are ultimately fatal Not transmitted from person to person DIAGNOSTIC LABORATORY TESTS A. Specimens, Microscopic Examination, and Culture Specimens include: o Cerebrospinal fluid (CSF) o Tissue o Exudates o Sputum o Blood o Cutaneous scrapings o Urine For direct microscopy, specimens are often examined in wet mounts, both directly and after mixing with India ink, which delineates the capsule Cryptococcus (India ink) NOTE TAKER: BALDOS | FERRER | PADAYAO B. Serology Tests Latex slide agglutination test or enzyme immunoassay (EIA) for cryptococcal antigen is positive in 90% of patients with cryptococcal meningitis With effective treatment, the antigen titer drops— except in AIDS patients, who often maintain high antigen titers for long periods TREATMENT Combination therapy of amphotericin B and flucytosine o Has been considered the standard treatment for cryptococcal meningitis Amphotericin B (with or without flucytosine) o Curative in most non-AIDS patients EPIDEMIOLOGY AND ECOLOGY Bird droppings (particularly pigeon droppings) enrich for the growth of C. neoformans and serve as a reservoir of infection In addition to patients with AIDS or hematologic malignancies, patients being maintained on corticosteroids are highly susceptible to cryptococcosis ASPERGILLOSIS Spectrum of diseases that may be caused by a number of Aspergillus species Aspergillus species o Ubiquitous saprobes in nature Aspergillus fumigatus o Most common human pathogen Many others may cause disease, including: o Aspergillus flavus o Aspergillus niger o Aspergillus terreus o Aspergillus lentulus Mold produces abundant small conidia that are easily aerosolized Following inhalation of these conidia, atopic individuals often develop severe allergic reactions to the conidial antigens In immunocompromised patients— especially those with leukemia, stem cell transplant patients, and individuals taking corticosteroids— the conidia may germinate to produce hyphae that invade the lungs and other tissues MORPHOLOGY AND IDENTIFICATION Grow rapidly, producing aerial hyphae that bear characteristic conidial structures: long conidiophores with terminal vesicles on which phialides produce basipetal chains of conidia Species are identified according to morphologic differences in these structures, including the size, shape, texture, and color of the conidia Page 5 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES o Some patients are asymptomatic; others develop cough, dyspnea, weight loss, fatigue, and hemoptysis o Localized, noninvasive infections (colonization) by Aspergillus species may involve the nasal sinuses, ear canal, cornea, nails Aspergillus fumigatus. (a, b) Seven days colonies of autumn (A.PZ1) and spring (A.BZ1) isolates on MEA; (c, d) Seven days colonies of autumn (A.PZ1) and spring (A.BZ1) isolates on CYA; (e) (f) conidiophores; (g) vesicle and phialides; (h, i) conidiophores with conidia CLINICAL FINDINGS A. Allergic Forms In some atopic individuals, development of IgE antibodies to the surface antigens of Aspergillus conidia elicits an immediate asthmatic reaction upon subsequent exposure In others, the conidia germinate, and hyphae colonize the bronchial tree without invading the lung parenchyma ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS o Defined as asthma, recurrent chest infiltrates, eosinophilia, and both type I (immediate) and type III (Arthus) skin test hypersensitivity to Aspergillus antigen Many patients produce sputum with Aspergillus and serum precipitins. They have difficulty breathing and may develop permanent lung scarring Normal hosts exposed to massive doses of conidia can develop EXTRINSIC ALLERGIC ALVEOLITIS B. Aspergilloma and Extrapulmonary Colonization ASPERGILLOMA o Occurs when inhaled conidia enter an existing cavity, germinate, and produce abundant hyphae in the abnormal pulmonary space o Patients with previous cavitary disease (eg, tuberculosis, sarcoidosis, and emphysema) are at risk NOTE TAKER: BALDOS | FERRER | PADAYAO C. Invasive Aspergillosis Following inhalation and germination of the conidia, invasive disease develops as an acute pneumonic process with or without dissemination. Symptoms include fever, cough, dyspnea, and hemoptysis Hyphae invade the lumens and walls of blood vessels, causing thrombosis, infarction, and necrosis From the lungs, the disease may spread to the gastrointestinal tract, kidney, liver, brain, or other organs, producing abscesses and necrotic lesions Without rapid treatment, prognosis is grave Persons with less compromising underlying disease may develop chronic necrotizing pulmonary aspergillosis, which is a milder disease DIAGNOSTIC LABORATORY TESTS A. Specimens, Microscopic Examination, and Culture Sputum, other respiratory tract specimens, and lung biopsy tissue provide good specimens. On direct examination of sputum with KOH or calcofluor white or in histologic sections, the hyphae of Aspergillus species are hyaline, septate, and uniform in width (about 4 μm) and branch dichotomously Aspergillus species grow within a few days on most media at room temperature Invasive aspergillosis. (Left) Uniform, branching septate hyphae (ca. 4 μm in width) of Aspergillus fumigatus in lung tissue stained with Gomori methenamine silver. 400×. (Right) Similar preparation with Grocott stain. 1000×. TREATMENT Aspergilloma is treated with itraconazole or amphotericin B and surgery Invasive aspergillosis requires rapid administration of either the native or lipid formulation of amphotericin B or voriconazole, often supplemented with cytokine immunotherapy (eg, granulocyte-macrophage colonystimulating factor or interferon) Allergic forms of aspergillosis are treated with corticosteroids Page 6 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES EPIDEMIOLOGY AND CONTROL For persons at risk for allergic disease or invasive aspergillosis, efforts are made to avoid exposure to the conidia of Aspergillus species Some patients at risk for invasive aspergillosis are given prophylactic low-dose amphotericin B or itraconazole Most bone marrow transplant units employ: o Filtered air-conditioning systems o Monitor airborne contaminants in patients’ rooms o Reduce visiting o Institute other measures to isolate patients and minimize their risk of exposure to the conidia of Aspergillus and other molds MUCORMYCOSIS (ZYGOMYCOSIS) Opportunistic mycosis caused by a number of molds classified in the order Mucorales Fungi are ubiquitous thermotolerant saprobes Pathogens are species of the genera: o Rhizopus o Rhizomucor o Lichtheimia o Cunninghamella o Mucor Most prevalent agent: Rhizopus oryzae RHINOCEREBRAL MUCORMYCOSIS o Major clinical form o Results from germination of the sporangiospores in the nasal passages and invasion of the hyphae into the blood vessels, causing thrombosis, infarction, and necrosis o Can progress rapidly with invasion of the sinuses, eyes, cranial bones, and brain Blood vessels and nerves are damaged, and patients develop facial edema, bloody nasal exudate, and orbital cellulitis Thoracic mucormycosis follows inhalation of the sporangiospores with invasion of the lung parenchyma and vasculature In both locations, ischemic necrosis causes massive tissue destruction Rhinocerebral mucormycosis: Necrotic tissue on the face NOTE TAKER: BALDOS | FERRER | PADAYAO Direct examination or culture of nasal discharge, tissue, or sputum will reveal broad hyphae (10–15 μm) with uneven thickness, irregular branching, and sparse septations These fungi grow rapidly on laboratory media, producing abundant cottony colonies Treatment consists o Aggressive surgical debridement o Rapid administration of amphotericin B Many patients survive, but there may be residual effects such as partial facial paralysis or loss of an eye Mucormycosis (Left) Broad, ribbon-like sparsely septate hyphae (10–15 μm in width) of Rhizopus oryzae in lung tissue. H&E 400×. (Right) Similar histopathologic specimen, stained with Gomori methenamine silver. 1000×. PNEUMOCYSTIS PNEUMONIA P. jiroveci causes pneumonia in immunocompromised patients; dissemination is rare For years, P. jiroveci was thought to be a protozoan, but molecular biologic studies have proved that it is a fungus with a close relationship to ascomycetes Pneumocystis species are present in the lungs of many animals (rats, mice, dogs, cats, ferrets, rabbits) but rarely cause disease unless the host is immunosuppressed P. jiroveci is the human species Pneumocystis carinii is found only in rats Until the AIDS epidemic, human disease was confined to interstitial plasma cell pneumonitis in malnourished infants and immunosuppressed patients (corticosteroid therapy, antineoplastic therapy, and transplant recipients) Prior to the introduction of effective chemoprophylactic regimens, it was a major cause of death among AIDS patients Chemoprophylaxis resulted in decrease in the incidence of pneumonia, but infections are increasing in other organs, primarily the spleen, lymph nodes, and bone marrow P. jiroveci o Morphologically distinct forms: thin-walled trophozoites and cysts, which are thick-walled, spherical to elliptical (4–6 μm), and contain four to eight nuclei o Cysts can be stained with silver stain, toluidine blue, and calcofluor white o In most clinical specimens, the trophozoites and cysts are present in a tight mass that probably reflects their mode of growth in the host Page 7 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES P. jiroveci o Surface glycoprotein that can be detected in sera from acutely ill or normal individuals o Extracellular pathogen o Growth in the lung is limited to the surfactant layer above the alveolar epithelium o In non-AIDS patients, infiltration of the alveolar spaces with plasma cells leads to INTERSTITIAL PLASMA CELL PNEUMONITIS Pneumocystis jirovecii cysts in methenamine silver stained bronchoalveolar lavage smear specimen To establish the diagnosis of Pneumocystis pneumonia, specimens of bronchoalveolar lavage, lung biopsy tissue, or induced sputum are stained and examined for the presence of cysts or trophozoites A specific monoclonal antibody is available for direct fluorescent examination of specimens Pneumocystis pneumonia is not usually seen until the CD4 lymphocyte count drops below 400/μL Acute cases of Pneumocystis pneumonia o Treated with trimethoprim–sulfamethoxazole or pentamidine isethionate Prophylaxis can be achieved with daily trimethoprim– sulfamethoxazole or aerosolized pentamidine No natural reservoir has been demonstrated, and the agent may be an obligate member of the normal flora Persons at risk are provided with chemoprophylaxis PENICILLIOSIS Caused by a dimorphic mold, Talaromyces marneffei, which was originally thought to be a species of Penicillium. Talaromyces marneffei o Opportunistic pathogen that is endemic in several regions of Southeast Asia, including southeastern China, Thailand, Vietnam, Indonesia, Hong Kong, Taiwan, and the Manipur state of India At ambient temperatures, the mold form grows rapidly to develop a green-yellow colony with a diffusible reddish pigment Septate, branching hyphae produce aerial conidiophores bearing phialides and basipetal chains of conidia NOTE TAKER: BALDOS | FERRER | PADAYAO Talaromyces marneffei. (a) On Sabouraud glucose agar, after 6 days of incubation at room temperature, colonies are yellowish green with diffusing red pigment. (b) The conidiophores are usually biverticillate. Oval, smooth-walled conidia are produced in chains. (c) On Sabouraud glucose agar, after 6 days of incubation at 37 °C, colonies are yeast-like and creamy. Diffusing red pigment is no longer observed. (d) In Sabouraud glucose broth, after 3 days of incubation at 37 °C with shaking at 250 rpm, the fungus grows as short hyphae composed of undissociated arthroconidia. (e) In yeast nitrogen base supplemented with 1% mycological peptone, after 3 days of incubation at 37 °C with shaking at 250 rpm, arthroconidiation is not observed. Instead, the fungus grows as individual yeast-like cells and divides by fission and this mode of growth resembles the in vivo situation. Clinical manifestations include: o Fungemia o Skin lesions o Systemic involvement of multiple organs, especially the reticuloendothelial system Early signs and symptoms are nonspecific and may include cough, fever, fatigue, weight loss, and lymphadenopathy In tissue, the hyphal forms convert to unicellular yeast-like cells (2 × 6 μm) that divide by fission. Major risk for infection: o Immunodeficiency due to HIV/AIDS o Tuberculosis o Corticosteroid treatment o Lymphoproliferative diseases 70% of patients, with or without AIDS, develop cutaneous or subcutaneous papules, pustules, or rashes, which are often located on the face. From specimens of skin, blood, or tissue biopsies, the diagnosis can be established by microscopic observation of the yeast-like cells and positive cultures. Treatment usually entails a defined course of amphotericin B followed by itraconazole Without treatment, the mortality has exceeded 90% Page 8 | 9 PCC SOM 2026 MICROBIOLOGY F.04 OPPORTUNISTIC MYCOSES CHECKPOINT 1. Most prevalent systemic mycosis A. Candidiasis B. Cryptococcosis C. Aspergillosis D. Mucormycosis 2. Yeast colonies with the presence of pseudohyphae A. Candidiasis B. Cryptococcosis C. Aspergillosis D. Mucormycosis 3. Widespread use of fluconazole has precipitated the emergence of more azole-resistant species EXCEPT: A. Candida glabrata B. Candida krusei C. Candida lusitaniae D. Candida tropicalis 4. Candida associated with Global emergence of a multidrug-resistant species A. Candida albicans B. Candida parapsilosis C. Candida glabrata D. Candida auris 5. Critical host defense against systemic candidiasis is an adequate number of functional: A. Eosinophils B. Basophils C. Neutrophils D. Monocytes 6. Produces BLUE colonies on CHROMagar A. Candida albicans B. Candida tropicalis C. Candida glabrata D. Candida krusei 7. Major clinical manifestation cryptococcosis A. ACUTE MENINGITIS B. SUBACUTE MENINGITIS C. CHRONIC MENINGITIS D. NOTA 8. Stain used to visualize the capsule of Cryptococcus neoformans A. India Ink B. Ireland Ink C. Indonesia Ink D. Philippine Ink 9. Serve as enrichment for growth and also as a reservoir of Cryptococcus neoformans infection A. Dog droppings B. Cat droppings C. Chicken droppings D. Pigeon droppings 10. Among the various Aspergillus species, which is the most common human pathogen A. Aspergillus fumigatus B. Aspergillus flavus NOTE TAKER: BALDOS | FERRER | PADAYAO 11. 12. 13. 14. 15. 16. 17. 18. C. Aspergillus niger D. Aspergillus terreus Arthus skin test hypersensitivity to aspergillus antigen A. Type I B. Type II C. Type III D. Type IV Occurs when inhaled conidia enter an existing cavity, germinate, and produce abundant hyphae in the abnormal pulmonary space A. Extrinsic allergic alveolitis B. Aspergilloma C. Allergic bronchopulmonary aspergillosis D. Invasive Aspergillosis Major clinical form of mucormycosis A. Rhinocerebral mucormycosis B. Thoracic mucormycosis C. Pulmonary mucormycosis D. Cutaneous mucormycosis Treatment for mucormycosis include the following EXCEPT: A. Aggressive surgical debridement B. Rapid administration of amphotericin B C. Rapid administration of ketoconazole D. NOTA Cysts of P. jiroveci can be stained with the following EXCEPT A. Silver stain B. Toluidine blue C. Calcofluor white D. Acridine orange Pneumocystis pneumonia is not usually seen until the CD4 lymphocyte count drops below A. 550/μL B. 500/μL C. 450/μL D. 400/Μl Clinical manifestations of penicillosis include: A. Fungemia B. Skin lesions C. Systemic involvement of multiple organs, especially the reticuloendothelial system D. AOTA Major risk for Penicillosis infection: A. Immunodeficiency due to HIV/AIDS B. Tuberculosis C. Corticosteroid treatment D. Lymphoproliferative diseases E. AOTA 1A 2A 3D 4D 5C 6B 7C 8A 9D 10A 11C 12B 13A 14C 15D 16D 17D 18E Page 9 | 9