Australian Society of CytologyCEC Resources
Respiratory Cytology Multiple Choice - Answers
Answer B is correct.
Cellular changes most suggestive of cytomegalovirus (CMV) include nuclear and cytoplasmic inclusions, 'owls-eye' appearance and cytomegaly.
Multinucleation is not a feature of CMV but is seen in herpes virus infection. Cilia is not usually discernible on cells infected with CMV or herpes but can be seen in adenovirus infections. CMV is characterised by nuclear and cytoplasmic inclusions whereas in herpes infection only nuclear inclusions are seen.
Question 2.
Answer C is correct.
Ciliocytophthoria is a cellular change characterised by degenerate columnar cell nuclei and detached cytoplasm with cilia.
Intact columnar cells are not a feature of the condition and inclusions are identified in the nucleus not the cytoplasm. The cells do not have a repair-like appearance.
Question 3.
Answer B is correct.
A diagnosis of Mycobacterium tuberculosis is suggested if acid fast bacilli, a granulomatous reaction and negative images of bacilli are seen.
Gram positive branching filaments and sulphur granules are features of Actinomyces israelii whereas ciliocytophthoria is usually seen in viral infections. Microcalcifications are seen in a range of conditions but have been especially described in tuberculous lesions.
Question 4.
Answer A is correct.
Actinomyces israelii is characterised by gram positive branching filaments and suphur granules.
Branching beaded filaments and 'chinese characters' are seen in Nocardia asteroides. The Warthin-Starry and Dieterle procedures are useful in identifying organisms| which stain poorly with gram and inconsistently with giemsa. These procedures can be used to identify the small bacilli of the genus Legionella.
Question 5.
Answer C is correct.
Coccidioides immitis is characterised by thick walled spherules containing numerous endospores.
Blastomycosis dermatitidis is typified by thick refractile double-contoured walls and single broad based buds. Cryptococcus neoformans is the only pathogenic fungus which produces capsular material demonstrated with mucicarmine or PAS. Single tear drop budding is usually identified.
Question 6.
Answer C is correct.
The differential diagnosis of pulmonary histoplasmosis includes all of the stated infections except Aspergillus fumigatus and mucomycosis. These fungal infections are typified by thick hyphae.
The distinction from yeast forms of Torulopsis glabrata may be difficult and require immunofluorescent techniques. In GMS stains, cysts of Pneumocystis carinii may resemble H capsulatum but the former are usually larger, have a central staining body and do not bud. Leishmania and Toxoplasma can also resemble H capsulatum but routine fungal stains are helpful in excluding these parasites.
Question 7.
Answer B is correct.
Broad based budding and thick double contoured walls are features of B dermatitidis.
C neoformans has a thick mucinous capsule and tear drop budding. H capsulatum is typified by the presence of uniform spherical-oval yeast-like cells in the cytoplasm of macrophages. The organism is uninucleate and can have single buds. Broad based budding or thick double contoured walls are not features of this organism.
Question 8.
Answer C is correct.
Fungi within the genera Mucor are characterised by broad pleomorphic hyphae which are thin walled, delicate and pauciseptate.
Aspergillus is characterised by long, uniform and septate hyphae with progressive and dichotomous branching. Mycelium containing swollen or globose hyphae are also a feature of this fungus.
Question 9.
Answer A is correct.
The liberated endospores of C immitis most resemble H capsulatum.
Poorly encapsulated forms of C neoformans can be mistaken for H capsulatum but usually some capsular material can be to assist in diagnosis. C neoformans is much larger than H capsulatum. B dermatitidis does not produce spores. The organism has a thick refractile double-contoured wall and shows broad based budding.
Question 10.
Answer B is correct.
Pseudohyphae seen in Candidiasis are formed by elongation of budding yeast forms and constriction of hyphae at point of attachment.
True hyphae are those hyphae which develop from spores. Bulbous swelling at the ends of hyphae segments is not a feature of pseudohyphae.
Question 11.
Answer C is correct.
The hyphae of the contaminant alternaria can be distinguished from aspergillus by all the features listed except the presence of thin walled pauciseptate hyphae with branching oriented at right angles. These features are found in mucomycosis.
Question 12.
Answer C is correct.
Pneumocystis carinii can be diagnosed by identifying cyst forms and trophozoites. An intra-alveolar exudate is also seen.
Broad based budding and thick cellular walls are features of B dermatitidis. Capsular material is seen in C neoformans
Question 13.
Answer C is correct.
Differential diagnosis of P carinii includes all the infections listed except B dermatitidis. B dermatitidis is much larger than P carinii and has thick refractile double contoured walls and broad based budding. Red blood cells can mimic the organism, especially in overstained GMS preparations.
Fungi of the genera Candida and Torulopsis may resemble P carinii in size and shape. The demonstration of budding and absence of a central staining body can assist in diagnosis. Liberated endospores of C immitis are approximately the same size as P carinii. Although these endospores do not bud they fail to show a central staining body with GMS. H capsulatum is usually smaller than P carinii but features helpful in diagnosis include its intracellular localisation and budding.
Question 14.
Answer C is correct.
The cysts of P carinii are best detected by all the stains listed except PAP and H&E. GMS, PAS, Toluidine blue and Gram-Weigert are the stains of choice and identify the cyst wall.
Question 15.
Answer A is correct.
Differential diagnosis of Toxoplasma gondii includes all the infections listed except Strongloides stercoralis and Echinococcus granulosus. S stercoralis present as larva measuring 400-500 in length with a characteristic notched tail. Hooklets, protoscolices and pieces of laminated cell wall confirm the diagnosis of E granulosus.
Question 16.
Answer C is correct.
Tumour cells surrounding cylindric cores of hyaline basal lamina material suggest a diagnosis of Adenoid cystic carcinoma.
Diagnosis of Chondroid hamatoma is based on the recognition of mature cartilage and/or fibromyxomatous fragments. Sheets of bronchial epithelium and fat may also be present. Carcinoids are composed of small round to oval nuclei with scant amounts of cytoplasm. The cells show poor cohesion and single cells and small cell clusters predominate. Hyaline basal lamina material is not identified in this tumour.
Question 17.
Answer A is correct.
A diagnosis of Chondroid hamartoma is based on the recognition of all the following features listed except intranuclear cytoplasmic pseudo-inclusions. These structures are usually found in papillary tumours.
Question 18.
Answer A is correct.
Ultrastructural identification of short microvilli, rootlets and core filaments may suggest a diagnosis of metastatic colonic adenocarcinoma.
Premelanosomes and melanosomes (type I and II) are seen in electron microscopic examination of malignant melanoma. Malignant Fibrous Histiocytoma is distinguished by the presence of histiocytic or myofibroblastic differentiation at the ultrastructural level. The cells also contain lysosomes and fat droplets.
Question 19.
Answer B is correct.
Tumour cells exhibiting positive immunostaining for S-100, HMB-45 and vimentin would suggest a diagnosis of malignant melanoma.
Question 20.
Answer C is correct.
Clear cell appearance can be identified in all the tumours listed except Non-Hodgkins lymphoma. The tumour is composed of malignant lymphoid cells with scant amounts of cytoplasm.
Return to: This Question
