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Amyloidosis
is a rare disease complex characterized by extracellular deposition
of insoluble fibre protein material which takes up Congo red stain and
exhibits apple green bifringence when examined under polarized light.
Although it is usually seen in a systemic form however 10-20% of cases
can be localized. Men are affected more than females and the mean age
of presentation is 55-60 years. Three types of systemic amyloidosis
are known namely the familial type, secondary type and primary or idiopathic
type. There are three forms of primary pulmonary amyloidosis viz tracheobronchial,
nodular-parenchymal and diffuse parenchymal or alveolar septal. We present
the radiological features of a case of diffuse parenchymal form of amyloidosis
which is the least common form of respiratory amyloidosis and has a
poor prognosis. |
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INTRODUCTION |
Amyloidosis
is a disease of unknown aetiology, although it is believed to represent
a derangement of immunoregulation. The amyloid protein is relatively
resistant to proteolytic digestion. This causes accumulation of the
extracellular protein followed by compromise in the organ function. |
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CASE
REPORT |
 
 
A 66 yr old male presented with signs and symptoms of progressively
increasing peripheral neuropathy and bilateral oedema feet. Blood investigations
revealed a raised serum globulin level and increased ESR. X-ray chest
taken showed multiple radio opaque well defined nodules scattered in
both the lungs (Fig. 1). There was no hilar prominence, no areas of
consolidation and no areas of abnormal calcification seen. The visualised
bones were normal. A differential diagnosis of metastatic nodules, sarcoidosis,
silicosis and amyloidosis was given. However no occupational exposure
history was found.
Patient was further investigated for beta macroglobulin and electrophoresis
revealed an M protein in the serum leading to the diagnosis of monoclonal
gamma-globulinopathy. 24 hour urine analysis revealed a protein loss
of 3 gm, suggestive of nephrotic syndrome. Kidney biopsy was done which
confirmed the diagnosis of amyloidosis (Fig. 2). 2D Echo showed no cardiac
involvement. Patient was treated with six cycles of cytotoxic therapy
(melphalan and prednisolone) which resulted in temporary disappearance
of the protein spike. After a period of one year, the patient developed
sudden onset dyspnoea, cough and expectoration for which a CT scan of
the chest was requested.
High resolution CT scan was performed on a Siemens Volume Zoom Multidetector
CT scanner. HRCT findings consisted of ill defined patchy areas of ground
glass attenuation with traction bronchiectasis and consolidative opacities
and peribronchial thickening in right lower lobe, and anterior segment
of the right upper lobe and apical segment of left lower lobe. Also
seen were multiple small well defined interstitial nodules (2-4 mm)
scattered in the lung parenchyma. These nodules showed areas of calcification
within. Also seen was tracheobronchial calcification (Fig. 3). Interestingly
there was bilateral pleural effusion (L > R) and a calcified lymph
node in the posterior mediastinal region (Fig. 4).
Patient expired within a period of 24 hours from respiratory failure.
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DISCUSSION |
Diffuse
parenchymal amyloidosis is the rarest but clinically most significant
as the patients are more likely to die of respiratory failure as in
our case.1 The most common physical finding in patients with primary
amyloidosis is pitting oedema, usually related to hypoalbuminaemia associated
with nephrotic syndrome. The major clue that helps to distinguish renal
amyloidosis from all other forms of the nephrotic syndrome is the finding
of a monoclonal protein in the serum or urine.2 Diffuse parenchymal
amyloidosis was further classified as with severe interstitial disease
without CHF; with CHF and senile cardiac amyloidosis.3 Radiologically
seen are nonspecific interstitial and alveolar opacities which may calcify
or show frank ossification. Thus pulmonary deposition of amyloid is
widespread involving small blood vessels and the pulmonary interstitium.1
In our case we observed similar findings of ill-defined patchy areas
of ground glass opacities with small calcific interstitial nodules scattered
in lung parenchyma along with peribronchial thickening, traction bronchiectasis
and bilateral pleural effusions. Pleural effusions appear to occur not
infrequently in patients with systemic amyloidois, 30% in one series.4
The cause of pleural effusion can be congestive cardiac failure, nephrotic
syndrome, liver failure or pleural amyloidosis.5 In our case the cause
of pleural effusion was attributed to the nephrotic syndrome. |
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CONCLUSION |
This
is a case of idiopathic systemic amyloidosis with pulmonary involvement.
The pulmonary amyloidosis manifested in the rare form of diffuse parenchymal
involvement and showed typical features of the same. Thus calcific small
pulmonary nodules in an elderly must raise a suspicion of amyloidosis
which has a poor prognosis. |
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REFERENCES |
| 1. |
Bruce
A Urban, Elliot K Fishman, Stanford M Goldman, et al. CT evaluation
of amyloid : spectrum of disease. Radiographics 1993; 13 : 1295-1308. |
| 2. |
Courtney
M Graham, Eric J Stern, Walter E Finkbeiner, et al. High resolution
CT appearance of diffuse alveolar septal amyloidosis. American
J Roentgenology 1992; 158 : 265-67. |
| 3. |
Morie
A Gertz, Robert A Kyle. Primary systemic amyloidosis - a diagnostic
primer. Mayo Clinic Proceedings 1989; 64 : 1505-19. |
| 4. |
Jean
Francois Cordier, Robert Loire, Jein Brune. Amyloidosis of the
lower respiratory tract. Chest 1986; 90 (6) : 827-31 |
| 5. |
Remy-Jardin
M, Beuscart R, Sault MC, et al. Subpleural micronodules in diffuse
infiltratives lung diseases: evaluation with thin section CT
scan. Radiology 1990; 177 : 133-39. |
| 6.. |
Mani
S Kavuru, James P Adamo, Muzaffar Ahmad, et al. Amyloidosis
and pleural diseases. Chest 1990; 98 (1) : 20-23. |
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HERPES
SIMPLEX IN CRITICAL CARE
‘HSV [herpes simplex virus] reactivation or infection
of the upper respiratory tract is frequent among patients in
intensive care’
Herpes simplex virus (HSV) is present in the throat of about
2-3% of adults in the general population, and is occasionally
detected in the respiratory tract of patients in intensive care.
Peggy bruynseels and colleagues did a prospective cohort study
to investigate the clinical importance of the virus in this
setting. The frequency of HSV in the throats of patients in
critical care was found to be as high as 22%, and 16% in the
lower respiratory tract. Presence of HSV in the throat was associated
with development of infection in the lower respiratory tract
and other factors.
Lancet Neurol 2003; 2 : 1536
THE STATIN WARS : WHY ASTRAZENECA MUST RETREAT
For AstraZeneca’s tactics in marketing its cholesterol-lowering
drug, rosuvastatin, raise disturbing questions about how drugs
enter clinical practice and what measures exist to protect
patients from inadequately investigated medicines.
Since there are no reliable data about efficacy and safety
and AstraZeneca is facing unusually acute commercial pressure
to force rosuvastatin into the market doctors should pause
before prescribing this drug. Physicians must tell their patients
the truth about rosuvastatin-that, compared with its competitors,
rosuvastatin has an inferior evidence base supporting its
safe use. AstraZeneca has pushed its marketing machine too
hard and too fast. It is time for McKillop to desist from
this unprincipled campaign.
The Lancet 2003; 362 : 1341
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