Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts 175


 
 Table of Contents  
CASE REPORT
Year : 2015  |  Volume : 6  |  Issue : 2  |  Page : 166-168

Alveolar microlithiasis: A rare cause of breathlessness since childhood


Department of Pulmonary Medicine, King George Medical University, Lucknow, Uttar Pradesh, India

Date of Web Publication13-Jul-2015

Correspondence Address:
Dr. Ram Awadh Singh Kushwaha
Department of Pulmonary Medicine, King George Medical University, Lucknow, Uttar Pradesh
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0975-9727.160702

Rights and Permissions
  Abstract 

Pulmonary alveolar microlithiasis (PAM) is an uncommon chronic disease characterized by calcifications within the alveoli and a paucity of symptoms in contrast to the imaging findings. It occurs sporadically and it is regarded as an autossomal recessive lung disease. The pathogenesis of PAM has yet to be elucidated. The disorder has a protracted course and there is no treatment available. We report a case of 21 years-old male who presented to us with complaint of exertional breathlessness since childhood. Diagnosis of pulmonary alveolar microlithiasis was made on the basis of clinical features and laboratory findings.

Keywords: Breathlessness, diffuse nodular shadows, pulmonary alveolar microlithiasis (PAM)


How to cite this article:
Kushwaha RA, Garg R, Kumar S, Verma SK, Mishra AK, Kapoor N. Alveolar microlithiasis: A rare cause of breathlessness since childhood. Muller J Med Sci Res 2015;6:166-8

How to cite this URL:
Kushwaha RA, Garg R, Kumar S, Verma SK, Mishra AK, Kapoor N. Alveolar microlithiasis: A rare cause of breathlessness since childhood. Muller J Med Sci Res [serial online] 2015 [cited 2020 Oct 27];6:166-8. Available from: https://www.mjmsr.net/text.asp?2015/6/2/166/160702


  Introduction Top


Pulmonary alveolar microlithiasis (PAM) is an uncommon chronic disease characterized by calcifications within the alveoli and a paucity of symptoms in contrast to the imaging findings. It occurs sporadically and it is regarded as an autossomal recessive lung disease. The pathogenesis of PAM has yet to be elucidated. The diagnosis is made usually on an incidental radiographic film in symptomless patients. There is a striking contrast between the paucity of signs and symptoms and the marked radiographic features. PAM is thought to be an autosomal recessive disease with <600 patients reported worldwide.


  Case Report Top


A 21 years old male, Non Smoker, Student R/O Sitapur presented to us with chief complaints of breathlessness since childhood. Breathlessness was non progressive in nature, occured only during exertion and was having no diurnal, postural or seasonal variation. It relieved on taking rest. There was no history of cough, chest pain, fever, hemoptysis, pedal edema. There was also no significant history of similar illness in the family. The respiratory and systemic examinations were totally within normal limits. All the routine blood investigations were also in the normal range. Chest X Ray PA view was done to search for the possible cause of breathlessness which was suggestive of bilateral diffuse nodular shadows more on lower lung field (sand storm lung) [Figure 1]. Spirometry was done which revealed increased FEV1/FVC with decreased FVC suggestive of restrictive defect.CT Scan Thorax was done to further evaluate the nodular shadows which showed bilateral multiple fine nodular lesions with basal predominance. Intra and interlobular septal thickening present in both lung fields. Foci of calcification noted in both lung fields, pericardium and mediastinal pleura. Black pleura sign was also present (due to small subpleural cyst) [Figure 2] and [Figure 3].
Figure 1: X-Ray chest showing bilateral diffuse nodular shadows more on lower zone (sand storm lung)

Click here to view
Figure 2: CT scan thorax showing foci of calcification in pericardium and mediastinal pleura

Click here to view
Figure 3: CT scan thorax showing bilateral multiple fine nodular lesions with basal predominance. Intra and interlobular septal thickening present in both lung fields. Black pleura sign also present (due to small subpleural cyst)

Click here to view


There was clinico radiological dissociation as the patient was quite asymptomatic despite of a lot of radiological findings. A provisional diagnosis of pulmonary alveolar microlithiasis (PAM) was made. To support our diagnosis HRUSG scrotum was done which was suggestive of left testicular calcification (testicular microlithiasis) [Figure 4]. This led us to confirm our diagnosis as PAM.
Figure 4: USG scrotum showing calcification of left testis

Click here to view



  Discussion Top


Pulmonary alveolar microlithiasis (PAM) is a rare disease of unknown etiology characterized by the widespread intra-alveolar deposition of laminated calcispherites in the lung. [1] Although the aetiology of PAM remains unclear, mutations of the SLC34A2 gene, which encodes a type IIb sodium-dependent phosphate co-transporter (NaP i -IIb), are considered to be the cause of the disease. [2] As a result of this mutation, the protein is unable to transport phosphorus ions from the alveolar space into type II pneumocytes, and this failure leads to the development of calcospherites in the alveolar space. [3] Most patients remain symptom-free for many years despite extensive radiological changes. [4],[5],[6] This condition was first described in 1856 by Friederich [7] as "Corpora-Amylacea in den lungen». Puhr in 1933 [8] used the term as Micralithasis alveolaris pulmonum. PAM is thought to be an autosomal recessive disease with <600 patients reported worldwide. [9] Most patients are between the ages 30 to 50 years at the time of diagnosis. Precise assessment of the history of alveolar microlithiasis is difficult. Therefore, in many cases, the diagnosis is made as an incidental radiographic film in symptomless patients. [10] There is a striking contrast between the paucity of signs and symptoms and the marked radiographic features. Patients eventually develop dyspnoea on exertion that limits their physical activity. Physical signs are conspicuous by their absence for most of its long course, though crackles, clubbing, cyanosis and signs of respiratory failure may be observed ultimately. Eventually respiratory failure and cor pulmonale supervene. Survival of 10-20 years is characteristic. Features on X ray Chest includes sand like calcified nodules (Sand Storm Lung). Pulmonary functions have been studied in a few patients with this disorder, and are usually normal or only slightly impaired for a long period following diagnosis. A restrictive ventilator defect (also seen in our patients) and diminished diffusing capacity are the most frequently reported abnormalities. This is largely related to alveolar filling. Bone scan or transbronchial lung biopsy are useful in confirming the diagnosis. [11],[12] CT scan of the chest reveals a diffuse infiltrative pattern. Findings of micronodular calcifications, Black pleura sign, interstitial abnormalities are typical. These interstitial changes correlate with pulmonary functions. 99mTc diphosphonate scan reveals increased uptake of the isotope throughout both lungs. [13] The disorder is slowly progressive and there is no definite therapy [14] So far no reversible treatment of this disorder is known. It has been proposed that a combined heart/lung transplant might be the possible way to prolong the life of the patients. Diphosphonates have been used to inhibit the microcrystal growth formation. [15] Nasal CPAP has shown to improve oxygenation in some. Although specific findings in HRCT scan could lead to diagnosis of PAM, other cases of diffuse pulmonary calcification should be considered for differential diagnosis, including metastatic pulmonary calcification, amyloidosis, and dendriform pulmonary ossification. [16] The knowledge of typical HRCT findings of this disease can lead to establishment of the diagnosis.


  Conclusion Top


In conclusion, PAM is a rare disease that can present with no symptoms. Characteristic HRCT findings can aid in diagnosis of this disease using less invasive procedures. Due to the inability to certify clear etiological and pathogenic factors, a therapeutic approach is difficult.

 
  References Top

1.
Moran CA, Hochholzer L, Hasleton PS, Johnson FB, Koss MN. Pulmonary alveolar microlithiasis: A clinicopathologic and chemical analysis of seven cases. Arch Pathol Lab Med 1997;121:607-11.  Back to cited text no. 1
    
2.
Hoshino H, Koba H, Inomata SI, Kurokawa K, Morita Y, Yoshida K, et al. Pulmonary alveolar microlithiasis: High-resolution CT and MR findings. J Comput Assist Tomogr 1998;22:245-8.  Back to cited text no. 2
    
3.
Fraser RS, Pare PD. Fraser and Pare′s Diagnosis of Diseases of The Chest. Vol. 2. Philadelphia, London: W. B. Saunders Company; 1970. p. 1131-4.  Back to cited text no. 3
    
4.
Mandi L, Simay A, Kelemen JT, Szabó A, Dayka A. Alveolar microlithiasis. Prax Pneumol 1968;22:230-7.  Back to cited text no. 4
    
5.
Sosman MC, Dodd GD, Jones WD, Pillmore GU. The familial occurrence of pulmonary alveolar microlithiasis. Amer J Roentgenol Radium Ther Nucl Med 1957;77:947-1012.  Back to cited text no. 5
    
6.
Friederich N. Zur Entwickelungsgeschichte der corpora amylacea in den Lungen. Virchows Arch Path Anat 1856;10:507. Quoted by Coetzee (1970).  Back to cited text no. 6
    
7.
Corut A, Senyigit A, Ugur SA, Altin S, Ozcelik U, Calisir H, et al. Mutations in SLC34A2 cause pulmonary alveolar microlithiasis and are possibly associated with testicular microlithiasis. Am J Hum Genet 2006;79:650-6.  Back to cited text no. 7
    
8.
Tachibana T, Hagiwara K, Johkoh T. Pulmonary alveolar microlithiasis: Review and management. Curr Opin Pulm Med 2009;15:486-90.  Back to cited text no. 8
    
9.
Moran CA, Hochholzer L, Hasleton PS, Johnson FB, Koss MN. Pulmonary alveolar microlithiasis. A clinicopathologic and chemical analysis of seven cases. Arch Pathol Lab Med 1997;121:607-11.  Back to cited text no. 9
    
10.
Tribel HJ, Von Hulset M, Schofer M. Fortgeschrittene microlithiasis pulmonum. Advanced Pulmonary Alveolar Microlithiasis. Rpntgen-blftter 1987;10:286-8.  Back to cited text no. 10
    
11.
Puhr L. Microlithiasis alveolaries pulmonum. Virchows Arch Path Anat 1933;290:156-60.  Back to cited text no. 11
    
12.
Jönsson ÅL, Simonsen U, Hilberg O, Bendstrup E. Pulmonary alveolar microlithiasis: Two case reports and review of the literature. Eur Respir Rev 2012;21:249-56.  Back to cited text no. 12
    
13.
Kang HW, Kim TO, Oh IJ, Kim YI, Lim SC, Choi YD, et al. A case of pulmonary alveolar microlithiasis. J Korean Med Sci 2011;26:1391-3.  Back to cited text no. 13
    
14.
Wallis C, Whitehead B, Malone M, Dinwiddie R. Pulmonary alveolar microlithiasis in childhood: Diagnosis by transbronchial biopsy. Pediatr Pulmonol 1996;21:62-4.  Back to cited text no. 14
    
15.
Göcmen A, Toppare MF, Kiper N, Büyükpamukcu N. Treatment of pulmonary alveolar microlithiasis with a diphosphonate - preliminary results of a case. Respiration 1992;59:250-2.  Back to cited text no. 15
    
16.
Chung MJ, Lee KS, Franquet T, Müller NL, Han J, Kwon OJ. Metabolic lung disease: Imaging and histopathologic findings. Eur J Radiol 2005;54:233-45.  Back to cited text no. 16
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Case Report
Discussion
Conclusion
References
Article Figures

 Article Access Statistics
    Viewed2180    
    Printed46    
    Emailed0    
    PDF Downloaded191    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]