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Mark A. Rasmus MD, Albany Medical
Center, Albany, NY
G. Scott Worthen MD, National
Jewish Medical and Research Center, Denver, CO
PRESENTING COMPLAINT
The patient is a 34-year-old woman
who presented for an evaluation of her life-long asthma. Her asthma
was poorly controlled since childhood; her symptoms seemed to worsen
over the past three years. Over that period she has wheezed daily,
had numerous emergency department visits, required monthly visits
to her physician and required daily prednisone. Her symptoms were
minimal at night and were rarely exacerbated by exercise. The patient
was particularly concerned about longer recovery periods between
attacks. These attacks required hospitalization four times in the
five months preceding referral. She was diagnosed with radiologically
confirmed pneumonia three times in the year prior to referral. The
patient was evaluated at National Jewish Medical and Research Center
to confirm her diagnosis of asthma and to evaluate for atopy and
other allergic triggers.
Past medical history is significant
for eczema. The patient reported allergies since childhood, with
anaphylactic reactions to specific foods including nuts, fish and
raw eggs. There is no history of aspirin sensitivity or nasal polyposis.
She also has a history of gastroesophageal reflux disease diagnosed
by endoscopy. She suffers from osteopenia and cataracts related
to her chronic corticosteroid use.
Her surgical history is remarkable
for sinus surgery to correct her deviated septum as well as debulking
of concha bullosa.
Medications on admission included
prednisone, fluticasone MDI, salmeterol diskus, albuterol MDI/ nebs,
montelukast, theophylline, alendronate, calcium, lansoprazole and
azelastine nasal spray.
Family history is significant for
a sister with asthma, one child with atopic dermatitis and both
parents have allergic rhinitis.
The patient is a lawyer, married
and living in a suburb of Phoenix with two children. She is a life-long
nonsmoker, and rarely drinks alcohol which does not exacerbate her
symptoms. She has no pets and she follows many hypoallergenic precautions
in her home.
PHYSICAL FINDINGS
Physical exam revealed a blood pressure
of 122/68, pulse of 82, respiratory rate of 14 and oxygen saturation
of 97% on room air.
Patient was a pleasant white woman
with a cushingoid facies. Her HEENT exam was significant for pale
nasal mucosa without polyps and no conjunctival erythema was noted.
Oropharyngeal exam was unremarkable without palpable lymphadenopathy.
Cardiac exam was normal. Her chest was symmetric and normal to percussion
as well as palpation. On ascultation her lungs had expiratory wheezes
that were most prominent over the sternal notch. The wheeze was
loudest with forced expiration. No crackles were noted and her inspiratory
to expiratory ratio was within normal limits. Her skin revealed
numerous ecchymoses predominantly on her lower extremities and striae
on her abdomen. Abdominal, neurologic and extremities exam were
normal.
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TEST DATA
Hemogram and biochemical panels
were normal. Immunoglobulins were normal, and an A.M. cortisol
level of 4.7 mcg/dL was consistent with her corticosteroid
use. Steroid kinetics revealed normal absorption, conversion
and clearance of prednisone. Lymphocyte proliferation assay
revealed a suboptimal response to hydrocortisone with normal
lymphocyte suppression to dexamethasone, budesonide and fluticasone.
Skin testing revealed marked atopy to numerous grasses, trees,
weeds and household allergens, and an immediate response to
aspergillus fumigatus.
Pulmonary function tests an
isolated increased residual volume at 150% predicted. Flows
were within normal limits and did not change following bronchodilator
therapy. Diffusing capacity was above normal. Methacholine
challenge revealed no significant change in FEV1 or specific
airways conductance. Fiberoptic laryngoscopy was performed
immediately following the methacholine challenge, with normal
vocal cord function despite audible wheezing on forced expiration.
A high-resolution CT scan was
performed and this revealed mild bronchial wall thickening,
with no bronchiectasis, air trapping or other deformities.
Bronchoscopy revealed friable,
irritated mucosa and normal left sided airways. The right
middle lobe orifice was quite small, and the superior segment
of the right lower lobe was significantly deformed and was
only able to be entered with a deep inspiratory maneuver.
Bronchoalveolar lavage of the right middle lobe revealed normal
cell count and differential; however electron microscopy revealed
an increased number of Langerhans type macrophages with
pleomorphic structures noted to be attached to them. These
are ultrastructurally consistent with Mycoplasma pneumoniae.
BRONCHOMALACIA PRESENTING
IN ADULTHOOD
Discussion
Bronchomalacia is defined as
narrowing of the airway lumen by greater than 50 percent.
Severe airway collapse can lead to airflow limitation, chronic
infection and bronchiectasis. Frequently, the airflow limitation
is demonstrated by an expiratory notch during spirometry.
Bronchomalacia can be categorized
as either congenital or acquired and can be either diffuse
or localized. The congenital form usually presents
as an isolated finding in infancy, and most patients are asymptomatic
by two years of age. The acquired form usually affects
adults and is most commonly associated with relapsing polychondritis,
tracheostomies, endotracheal tubes, syphilis, crushing chest
trauma, and anastamotic sites following lung transplantation.
It is suggested that the acquired form is a result of a congenital
weakness of the fibrous tissue combined with chronic inflammatory
irritation. It is certainly possible that the abundant Langerhans
cells on BAL signify chronic inflammation.
Our patient exhibited near
total collapse of her affected airways during bronchoscopy,
as demonstrated in figures 1-4; however, some of the classic
spirometric findings were absent. The near normal spirometry
in our patient is most likely due to the distal, localized
nature of her disease.
Treatment strategies include
surgical stent placement for localized proximal lesions, and
other techniques aimed to prevent airway collapse. Pursed
lip breathing, continuous positive airway pressure (CPAP),
and expiration through a resistor apparatus have all been
used.
A combination of flutter valve
use, pursed lip breathing during exercise and nasal CPAP has
allowed our patient to be weaned from her corticosteroids
and asthma medications. She continues to remain free from
hospitalizations and episodes of pneumonia during her six
months following her diagnosis.
Conclusion
Bronchomalacia can simulate
asthma. Suggestive features include persistence of wheezing
despite aggressive bronchodilator therapy, poor response to
glucocorticoids, and negative methacholine challenge.
Diagnosis can be made with
either bronchoscopy or dynamic (inspiratory/expiratory) spiral
CT scan. Conservative treatment designed to improve airway
secretion clearance and stent collapsable airways can help
limit the complications of this disease, mainly chronic infection
and bronchiectasis or long-term corticosteroid use due to
a misdiagnosis as asthma.
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Figure
1 - Right middle lobe orifice during inspiration.

Figure
2 - Right middle lobe orifice during forced expiration

Figure
3 - Narrowed
orifice of superior segment of right lower lobe

Figure
4 - Electron microscopy of BAL; Langerhans type macrophages
(click on image for larger and closer view)
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