Find information on thousands of medical conditions and prescription drugs.


Lymphangioleiomyomatosis (LAM) is the result of disorderly smooth muscle proliferation throughout the bronchioles, alveolar septa, perivascular spaces, and lymphatics, resulting in the obstruction of small airways (leading to pulmonary cyst formation and pneumothorax) and lymphatics (leading to chylous pleural effusion). LAM occurs in a sporadic form, which only affects females, who are usually of childbearing age. LAM also occurs in patients who have tuberous sclerosis. more...

Amyotrophic lateral...
Bardet-Biedl syndrome
Lafora disease
Landau-Kleffner syndrome
Langer-Giedion syndrome
Laryngeal papillomatosis
Lassa fever
LCHAD deficiency
Leber optic atrophy
Ledderhose disease
Legg-Calvé-Perthes syndrome
Legionnaire's disease
Lemierre's syndrome
Lennox-Gastaut syndrome
Lesch-Nyhan syndrome
Leukocyte adhesion...
Li-Fraumeni syndrome
Lichen planus
Limb-girdle muscular...
Lipoid congenital adrenal...
Lissencephaly syndrome...
Liver cirrhosis
Lobster hand
Locked-In syndrome
Long QT Syndrome
Long QT syndrome type 1
Long QT syndrome type 2
Long QT syndrome type 3
Lung cancer
Lupus erythematosus
Lyell's syndrome
Lyme disease
Lysinuric protein...


The cause of the sporadic form of LAM is unknown. This type only affects women.

The proliferating smooth muscle that occurs the type of LAM seen in patients with tuberous sclerosis (TSC-LAM) has been shown to represent clones of the smooth muscle in those patients' renal angiomyolipomas, and thus is believed to represent metastases of this "benign" tumor. There is a female properandence to TSC-LAM. (reference: Henske EP. Metastasis of benign tumor cells in tuberous sclerosis complex. Genes, Chromosomes & Cancer. Dec. 2003. 38(4):376-81)


With LAM, there is diffuse replacement of the pulmonary parenchyma by thin-walled cysts measuring 2-20 mm in diameter, with equal involvement of upper and lower lung zones. On chest X-rays, superimposition of the cysts gives a reticulonodular pattern of interstitial lung disease. High-resolution CT of the chest is both more specific for the diagnosis, as well as better able to assess the degree of pulmonary involvement.


Without lung transplant, there is a 50-80% 5-year survival rate.


  • Worsening pulmonary insuffiency
  • Pneumothorax, secondary to rupture of a cyst into the pleural space
  • Chylous pleural effusions


The association of LAM with women of childbearing age suggests that hormonal stimulation plays a role in the disease process, and several approaches to treatment involve diminishing the effect of estrogen. At one time or another, therapeutic approaches have included

  • progesterone
  • oophorectomy
  • tamoxifen
  • gonadotropin-releasing hormone (GnRH) agnonists
  • androgen therapy

No therapy is clearly efficacious, and all have undesirable side-effects.

When pulmonary function deteriorates to the point where oxygenation is inadequate, lung transplantation is usually performed. Following lung transplant (usually unilateral), LAM patients have survival curves similar to other lung transplant patients.


The drug Sirolimus (also known as Rapamycin) is being investigated in clinical trials as a possible treatment. It has been shown to shrink angiomyolipomas in animals. For more information see this interview.


LAM Action (UK)

The LAM Foundation (US)


[List your site here Free!]

Lymphangioleiomyomatosis and SZ [[alpha].sub.1]-antitrypsin disease : a unique combination? - selected reports
From CHEST, 8/1/03 by Andrew L. Chan

We describe a case of a 37-year-old female ex-smoker with lymphangioleiomyomatosis and SZ [[alpha].sub.1]-antitrypsin disease who underwent successful bilateral sequential lung transplantation. While this disease combination has not been described previously, we recommend vigilance for the possibility of such combinations in patients with chronic lung disease. The possible mechanisms of interaction resulting from both disease processes are discussed.

Key words: chylothorax; COPD: lymphangioleiomyomatosis: matrix metalloproteinase: SZ [[alpha].sub.1]-antitrypsin disease

Abbreviations: A1AT = [[alpha].sub.1]-antitrypsin: LAM = lymphangioleiomyomatosis


[[alpha].sub.1]-Antitrypsin (A1AT) deficiency is the most common inherited metabolic disorder causing lug disease. (1) Although the ZZ phenotype, of A1AT deficiency has been clearly linked to an increased risk of emphysema, the clinical significance of the SZ phenotype has been less evident. (1) Some studies have suggested an increased risk of obstructive lung disease, (1,2) while others have not. (3,4) SZ heterozygosity appears to result in minimal, if any, clinical sequelae in nonsmokers with intermediate levels of A1AT. (3) However, exposure to cigarette smoke confers a significant risk of developing COPD in such patients, presumably by further accentuating the inherent elastase/ A1AT imbalance within the lung. (5) A1AT deficiency has been reported (6) in association with idiopathic pulmonary fibrosis. We describe the first report, to our knowledge, of biopsy-proven lymphangioleimyomatosis (LAM) in the setting of A1AT heterozygosity with the SZ phenotype. The possibility that the SZ phenotype may have further contributed to this patient's pulmonary pathology in the setting of LAM is intriguing, especially as their association has not been described previously.


A 37-year-old white woman was referred for consideration of lung transplantation. A presumptive diagnosis of LAM had been made 2 years prior, based on her clinical, physiologic, and radiologic findings.

Her history included 6 years of progressive dyspnea, exertional wheezing, and chest tightness, a 15-lb unplanned weight loss, and a chronic cough productive of milky sputum for 3 months. She smoked 1 cigarette daily from age 17 to 22 years. There was no personal or family history of seizures, mental retardation, or skin lesions, although a vague history of it sister having a low A1AT level was reported but could not be subsequently confirmed.

Physical examination revealed an alert woman with a BP of 100/80 mm Hg, a heart rate of 86 heats/min, a respiratory rate of 16 breaths/min, and a resting oxygen saturation level of 95% breathing room air. Abnormal physical findings included mild nasal congestion, a widened anterior/posterior thoracic diameter, depressed diaphragms with a diaphragmatic excursion of 2 cm, labored respirations, and use of accessory muscles of respiration with minor exertion. On chest auscultation, breath sounds were diminished, and expiration was prolonged with audible wheezing. No finger clubbing, cyanosis, peripheral edema, or cutaneous manifestations of tuberous sclerosis were noted. There were no cardiac murmurs, gallops, or parasternal heaves. The remainder of the physical examination findings was normal.

A summary of her pertinent laboratory data included the following. Arterial blood gas levels while breathing room air showed a pH of 7.46, a PC[O.sub.2], of 29 mm Hg, and a P[O.sub.2] of 65 mm Hg. The hematocrit was 43%, hemoglobin level was 15.1 g/dL, and a WBC count was 6,100 cells/[micro]L. The WBC differential count was normal, with 1% eosinophils. The IgE level was 23 U/mL, (normal range, 0 to 110 U/mL), Antinuclear antibody and rheumatoid antibody assays were negative. The lactate dehydrogenase level was elevated at 829 IU/L (normal range, 313 to 618 IU/L).

An ECG showed sinus rhythm and was consistent with a diagnosis of Wolff-Parkinson-White syndrome. An echocardiogram demonstrated normal-sized cardiac chambers, with normal left ventricular systolic function. A quantitative ventilation-perfusion scan of the lungs demonstrated matched, symmetric bilateral mid-zone ventilation and perfusion defects, with 50% perfusion to each lung.

A CT scan of the sinuses was normal. Posteroanterior and lateral chest radiographs demonstrated hyperinflation and increased interstitial marking with evidence of bilateral bullous disease. A high-resolution CT scan of the chest revealed multiple bilateral, diffuse, thin-walled cystic air spaces, ranging in size from a few millimeters to 3.5 cm in diameter, throughout the entire lung. In addition, there were some scattered linear scarring changes. The pulmonary arteries were of normal size (Fig 1).


Pulmonary function tests revealed an [FEV.sub.1] of 0.62 L (22% of predicted), an FVC of 2.0 L (61% of predicted), all [FEV.sub.1]/FVC ratio of 31%, a total lung capacity of 5.66 L (116% of predicted), mid a diffusing capacity of the lung carbon monoxide of 8.0 mL/min/mm Hg (42% of predicted). This was interpreted as being consistent with severe airflow obstruction. No significant bronchodilator response was noted. A 6-min walk test showed significant oxygen desaturation while breathing air from a resting baseline of 96% to a nadir of 85% during exercise. The total distance walked was 1,584 feet. Because of the persistent wheezing and a family history of possible A1AT deficiency, an A1AT level was measured, revealing an abnormally low value of 66 mg/dL (normal range, 90 to 180 mg/dL). Subsequent testing confirmed the presence of an SZ phenotype in this patient.

The patient's clinical course was complicated by bilateral pneumothoraces, requiring bilateral tube thoracostomies and, finally, bilateral surgical pleurodeses to close bilatera bronchopleural fistulas. During this latter procedure, a subpleural wedge biopsy of the left lung was performed, and the specimen showed lung parenchyma with multiple cystic spaces, occasionally lined by cells with plump avoid-to-round nuclei and moderate amounts of cytoplasm (Fig 2). These cells strongly stained with immunohistochemical markers for actin and HMB-45, and were diagnostic for LAM (Fig 3). Seventeen months ago, the patient underwent uncomplicated bilateral sequential lung transplantation and has since returned to full-time employment.



LAM is a rare interstitial lung disease that is characterized by an abnormal proliferation of smooth muscle-like cells, resulting in the progressive obstruction of airways, blood vessels, and lymphatics. Clinical features of LAM include progressive dyspnea, spontaneous pneumothoraces, and cough. Hemoptysis, chest pain, and chylothorax may be present. (7) The etiology of LAM is not known.

Among the pathology hallmarks of LAM are diffuse cystic changes with proliferation of smooth muscle cells. (8) Previous authors have hypothesized that these cystic lesions may develop as a result of airflow obstruction secondary to bronchiole and bronchiolar narrowing by the proliferating smooth muscle. (9,10) More recently, it has been noted that, at the periphery of the smooth muscle infiltrate. the degradation of elastic fibers and intense remodeling activity occur. These are likely related to an imbalance in the elastase/A1AT system similar to the probable pathogenesis of emphysema. (11) Indeed, Fukuda et al (12) proposed that the cystic lesions found in patients with LAM were the result of such degradation of elastic fibers from the mechanism outlined above. They observed that the proliferating smooth muscle cells contained electron-dense granules in the cytoplasm that, when released, may have contributed to the development of emphysema via the elastase pathway. Hayashi et al (13) showed increased immunoreactivity in the LAM cells of matrix metalloproteinase (MMP)-2, MMP-9, and MMP-1. As MMPs are capable of cleaving extracellular elastins and collagens, the authors suggested that it was an imbalance of MMPs and their inhibitors that was responsible for the cystic lesions in patients with LAM. Of note, Ohnishi et al (14) reported increased immunoreactivity to some MMPs, including MMP-2, in the lungs of non-LAM patients with emphysema, suggesting a significant role for the MMP-mediated extracellular matrix degradation pathway in the pathogenesis of emphysema.

Although A1AT is all inhibitor mainly of serine proteases, and does not inhibit MMP-2 and MMP-9 per se, (13) it is possible that MMPs may cleave a variety of nonextracellular matrix proteins including A1AT. (15) The inactivation of A1AT by LAM cell-derived MMPs in this ex-minimal smoker with a low serum A1AT level possibly could hasten parenchymal destruction and the development of emphysema.

While the current literature does not support a common etiology or genetic linkage between LAM and A1AT deficiency, the presence of these two conditions in our patient could produce severe airflow obstruction and cystic lung disease. It is also unclear whether A1AT augmentation therapy at this stage would be of benefit. (16) Further understanding of the genetic, biochemical, and molecular pathways in both LAM and A1AT deficiency may enable future novel therapies for these patients.

* From the University of California (Drs. Chan and Kwack), Davis Medical Center, Sacramento, CA; University of California (Dr. Jones), San Francisco, CA: University of Miami (Dr. Glassberg), Miami, FL; and Kaiser Permanente Medical Center (Dr. Gherman), San Francisco, CA.

Manuscript received December 18, 2002; revision accepted February 12, 2003.


(1) Lomas DA. Advances in genetics: alpha 1-antitrypsin deficiency. Eur Respir Rev 2000; 10:358-364

(2) Lieberman J, Winter B, Sastre A. Alpha 1-antitrypsin Pi-types in 965 COPD patients, Chest 1986; 89:370-373

(3) Alvarez-Granda L, Cabero-Perez MJ, Bustamante-Ruiz A, et al. PI SZ phenotype in chronic obstructive pulmonary disease. Thorax 1997; 52:659-661

(4) Hutchison DC, Tobin MJ, Cook PJ. Alpha 1 antitrypsin deficiency: clinical and physiological features in heterozygotes of Pi type SZ; a survey by the British Thoracic Association. Br J Dis Chest 1983; 77:28-34

(5) Turino GM, Barker AF, Brantly ML, et al. Clinical features of individuals with PI * SZ phenotype of alpha 1-antitrypsin deficiency: Alpha 1-Antitrypsin Deficiency Registry Study Group. Am J Respir Crit Care Med 1996; 154:1718-1725

(6) Hubbard R, Baoku Y, Kalsheker N, et al. Alpha1-antitrypsin phenotypes in patients with cryptogenic fibrosing alveolitis: a case-control study. Eur Respir J 1997; 10:2881-2883

(7) Johnson S. Rare diseases: 1. Lymphangioleiomyomatosis: clinical features, management and basic mechanisms. Thorax 1999; 54:254-264

(8) Sullivan EJ. Lymphangioleiomyomatosis: a review. Chest 1998; 114:1689-1703

(9) Conin B, Liebow AA, Friedman PJ. Pulmonary lymphangiomyomatosis: a review. Am J Pathol 1975; 79:348-382

(10) Carrington CB, Cugell DW, Gaensler EA, et al. lymphangioleiomyomatosis: physiologic-pathologic-radiologic correlations. Am Rev Respir Dis 1977; 116:977-995

(11) Kalassian KG, Doyle B, Kao P, et al. Lymphangioleiomyomatosis: new insights. Am J Respir Crit Care Med 1997; 155:1183-1186

(12) Fukuda Y, Kawamoto M, Yamamoto A, et al. Role of elastic fiber degradation in emphysema-like lesions of pulmonary lymphangiomyomatosis. Hum Pathol 1990; 21:1252-1261

(13) Hayashi T, Fleming MV, Stetler-Stevenson WG, et al. Immunohistochemical study of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in pulmonary lymphangioleiomyomatosis (LAM). Hum Pathol 1997; 28: 1071-1078

(14) Ohnishi K, Takagi M, Kurokawa Y, et al. Matrix metalloproteinase-mediated extracellular matrix protein degradation in human pulmonary emphysema. Lab Invest 1998; 78:1077-1087

(15) Shapiro SD, Senior RM. Matrix metalloproteinases: matrix degradation and more. Am J Respir Cell Mol Biol 1999; 20:1100-1102

(16) Sandhaus RA. Alpha(1)-antitrypsin deficiency therapy: pieces of the puzzle. Chest 2001; 119:676-678

Reproduction of this article is prohibited without written permission from the American College of Chest Physician (e-mail:

Correspondence to: Andrew Chan, MB, FCCP, 4150 V St, Suite 3400, Sacramento. CA 95817; e-mail:

COPYRIGHT 2003 American College of Chest Physicians
COPYRIGHT 2003 Gale Group

Return to Lymphangioleiomyomatosis
Home Contact Resources Exchange Links ebay