13
Respiratory Tract
Fig. 13.48
Cryptococcus neoformans.
The dark refractile appearance of
the yeast cells results from the trapping of air under the organism. Bronchial
washing (Papanicolaou x OI).
Fig. 13.50
Coccidioidesimmitis.
This field shows intact spherules
containing endospores, ruptured spherules, and free endospores. Note
the resemblance of the enlarging endospores to
Blastomyces derm atitidis.
Sputum (Papanicolaou x MP).
Fig. 13.49
Cryptococcus neoformans.
This field illustrates the typical
narrow-based budding and variation in cell size as well as prominent staining
of the capsule. Sputum (Papanicolaou x OI).
area within the organism possessing a refractile appearance is
frequently observed and is similar to that of the internal struc-
ture of a starch granule. We believe that this appearance is due to
the presence of trapped air within a depression in the wall of the
organism beneath the coverslip. It is well known from preparing
specimens of the female genital tract that if one does not exclude
all air as the coverslip is lowered onto the mounting medium,
bubbles of trapped air give a dark refractile appearance.
The inflammatory reaction provoked by
Cryptocococcus
may
be extremely slight, completely absent, or granulomatous. The
following case history is a fairly characteristic profile of patients
in whom
Cryptococcus
is diagnosed.
A 57-year-old man had been receiving large doses of steroid
medication for regional enteritis. He had gradually developed
increasing shortness of breath and cough. Radiographs of the
lung showed multiple pulmonary nodular densities. Metastatic
carcinoma was suspected. FNA showed the presence of typical
budding yeast forms of
C. neoformans.
These cytologic observa-
tions were confirmed by positive culture findings.
Pulmonary Coccidioidomycosis
Coccidioidomycosis is a chronic granulomatous infection most
frequently involving the lungs but rarely also spreading to other
organs in the body. The causative agent is the dimorphic fun-
gus
Coccidioides immitis.
Infection is by inhalation of the highly
infectious arthroconidia (arthrospores) formed by disarticula-
tion of mycelia in the soil. In the United States, coccidioides is
endemic in a number of southwestern states, including Califor-
nia, Arizona, New Mexico, Nevada, Utah, and Texas. It is also
endemic in certain parts of Central and South America.
Primary infection for an otherwise healthy individual may be
without symptoms, or the individual may present with an upper
respiratory tract infection or a lower respiratory tract infection
with cough, chest pain, fever, chills, night sweats, weakness,
and sputum production. Results of radiologic studies are usu-
ally nonspecific, showing infiltrates, consolidation, or pleural
effusion. The majority of these pulmonary infections resolve
spontaneously; however, a small number of patients experience
residual disease, including a pulmonary nodule, cavity, pro-
gressive pneumonia, and chronic pulmonary disease. Immu-
nocompromised patients and those with diabetes mellitus are
particularly prone to develop chronic disease.
The gross and histopathologic changes of pulmonary coc-
cidioidomycosis are characterized by granulomatous inflam-
mation, caseous necrosis, cavitation, and fibrosis. Thus, this
disease bears striking resemblance to pulmonary tuberculosis.
Histologic examination of tissues reveals the large spherules
containing endospores. Hyphal forms may occasionally also be
present.193,206
Spherules and endospores of
C. immitis
have been reported
in cytologic preparations of sputum, bronchial washings, and
FNAs.207,208 In Papanicolaou-stained material,
the spherule
appears as a nonbudding spheric, thick-walled structure meas-
uring 20-60 pm in diameter. Staining characteristics are variable
and of little aid in identification. The spherules may be empty
or may contain endospores. These are round, nonbudding struc-
tures measuring 1-5 pm in diameter (Fig. 13.50). It is not dif-
ficult to confuse the empty spherules with nonbudding forms
of
B. dermatitidis.
Arthrospores may occasionally be present in
sputum. The following case histories are illustrative.
323
previous page 320 ComprehensiveCytopathology 1104p 2008 read online next page 322 ComprehensiveCytopathology 1104p 2008 read online Home Toggle text on/off