| An Aspergillus species was recovered from a sputum specimen of a patient with X-ray evidence of fungal pneumonia. Microscopic examination did not permit a species identification. A small amount of vegetative mycelium was removed and a direct mount prepared. The features indicated by the red arrows in this image are associated with which Aspergillus species? | View Page |
| The hyaline mold illustrated in this photomicrograph can be identified as: | View Page |
| The spores produced by telomorphic forms of Aspergillus glaucus are: | View Page |
| The "birds on a fence" arrangement of uniform-sized, tear-shaped microconidia is characteristic of: | View Page |
| Illustrated in this photomicrograph are fruiting heads of Trichoderma species. Note the single, long, tapered phialides (red arrows), extending laterally from either side of the hyphae, one of the key identifying features of this fungus. Another hyaline mold that produces long tapered phialides is: | View Page |
| The fungus illustrated in this photomicrograph of a lactophenol blue-stained preparation was recovered from skin scrapings of a patient with tinea pedis. The most likely identification is: | View Page |
| Illustrated here is a single conidium of Microsporum canis. Note that the hilar cell appears fractured (short red arrow), where it was released from the stolon. Macroconidia having this so-called "break-away" cell are termed: | View Page |
| The hyaline saprobic fungus that has microscopic features similar to the mold form of Coccidioides immitis is: | View Page |
| The most helpful feature in differentiating the Zygomycetes from the other hyaline molds in the clinical mycology laboratory is: | View Page |
| Match each hyaline mold from the drop-down list to its corresponding microscopic and colony description. The microscopic appearance of the molds are illustrated in the image on the right. | View Page |
| Match the names of each of the fungal species listed in the drop-down box with the corresponding identifying structures illustrated in the photomicrographs: | View Page |
| A presumptive identification of the four genera of slower growing pathogenic dematiaceous molds can be made by observing specific types of conidiation. Match the names of the species of dematiaceous pathogenic fungi with the corresponding microscopic features illustrated in the photomicrographs: | View Page |
| Match the name of each fungal species listed in the drop-down box with its most likely corresponding morphologic feature. | View Page |
| The infrequently encountered mold that is represented by the photomicrograph begins as a gray-white colony that blackens with maturity as the hyphae become darkened and single, globose, black conidia are produced. This fungus can be identified as: | View Page |
| The multi-celled conidia of this dematiaceous mold are divided into cells by what are called distosepta (pseudosepta), indicating that the individual cells are surrounded by a sac-like wall that is distinct from the outer cell wall of the conidium. The identification of this mold is: | View Page |
| The type of sporulation of the dematiaceous mold that is illustrated in this photomicrograph is called: | View Page |
| The dematiaceous fungus that may produce both acrotheca and rhinocladiella types of sporulation is: | View Page |
| The chain of conidia illustrated in this photomicrograph, with the deep-staining truncated bases, are called annelloconidia, and are most characteristic of: | View Page |
| In this photomicrograph are observed several background dematiaceous hyphae within which is seen a long, flask-shaped, tapered phialide (arrow) that has a flat saucer-like terminus. This feature is most characteristic of: | View Page |
| The chief microscopic feature possessed by Ulocladium species by which it can be differentiated from the close look-alike Stemphilium species is: | View Page |
| Match each of the names of the dimorphic fungal species with its corresponding mold form as seen in the photomicrographs. | View Page |
| The colonies shown in the upper image were obtained on blood agar from a sputum specimen after 10 days incubation at 30°C. The lower image is a photomicrograph of a lactophenol blue mount made from a portion of the colony. The diagnosis is: | View Page |
| The growth of the colonies shown in the upper image was obtained on blood agar from a sputum specimen after 8 days of incubation at 30°C. The lower image is a photomicrograph of a lactophenol blue mount made from a portion of the colony. The diagnosis is: | View Page |
| The colonies shown in the upper image, obtained from a biopsy of an ulcerating skin lesion of the arm, are growing on agar slants of Sabouraud's dextrose agar. The lower image is a photomicrograph of a lactophenol blue mount made from a portion of the colony growing in the left slant. The diagnosis is: | View Page |
| Match each of the fungal species listed below with the appropriate category, indicating whether or not it has the capability of producing pseudohyphae on cornmeal agar. | View Page |
| Match the following: | View Page |
| Fungal hyphae Tubular filaments of fungi called hyphae may also be seen in a direct smear. Hyphae stain Gram positive and may branch or intertwine. Parasites can also be identified with the Gram stain, although it is not as sensitive as the special stains used for parasites. The Gram stain reaction and appearance can be used to identify most cellular material seen in a direct smear. The crystal violet may precipitate and can be seen on the slide. If the stain has precipitated, it must be refiltered before use.
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| Which of the following cells are about the same size as red cells? | View Page |
| Match the Gram stain reaction for each of the following nonbacterial elements. | View Page |
| In this slide, which structure or structures are present? (Choose ALL of the correct answers) | View Page |
| In this slide, which structure or structures are present? (Choose ALL of the correct answers) | View Page |
| In this slide, what is the conspicuous structure? | View Page |
| Overall Procedure View control smears under oil immersion. If the control smears stained correctly, read the remainder of the smears.Look at the direct smear macroscopically to locate the stained area.Examine the direct smear under oil immersion and find an area that is properly decolorized.Examine at least ten fields in an area that is properly decolorized.Identify the following nonbacterial cell types: epithelial cells, white blood cells, red blood cells, yeast and hyphae.Look for microorganisms and record their characteristics.Quantitate each type of element found and record on the work card.Interpret the direct smear result.Report the direct smear finding.
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| Size and Appearance of Cellular Elements Epithelial cells are larger than white blood cells and red blood cells, and contain a single nucleus. White blood cells (pus cells) usually show a segmented nucleus. Red blood cells are 1/2 to 2/3 as large as white blood cells, contain no nucleus, and are gram negative.Hyphae are gram positive tubular filamentous fungal elements which may show branching or intertwining. Yeast cells are round to oval, often budding, gram positive fungal elements, about the same size as RBCs. They are generally much larger than bacteria.
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| Significance of Specific Findings: Epithelial cells in large numbers within sputum smears means that the specimen is predominantly oral saliva, rather than true sputum from the lung. Epithelial cells in urine smears indicate that the sample has been contaminated by organisms found on the vulva or distal urethra. Bacteria found near or on epithelial cells are usually normal contaminating bacterial flora.White blood cells indicate inflammation and possible infection. The direct smear examination should focus within and around these cells.Red blood cells in a direct smear are not usually significant.Yeast may be present as normal flora in upper respiratory tract or genital tract. They may be significant if they predominate, or if budding yeast forms are seen.Hyphae are more likely to indicate the presence of fungal infection, but this determination requires correlation with clinical findings.Bacteria found in spinal fluid, blood, tissue and specimens from other sterile sites are always significant.Body fluids which are normally sterile must be examined carefully. If only one organism per oil immersion field is identified, then there are about 105 organisms per mL present in the sample! Bacteria observed in specimens from the throat, genital tract and other areas containing normal flora suggest infection only if their composition and type varies significantly from the norm. | View Page |