Radiology
Chest radiographs of patients with PAM usually reveal bilateral diffuse micronodular calcifications, producing a "sandstorm” appearance that first involves the inferior portions and then the middle and upper portions of the lungs. High-resolution computed tomography
The most common findings on HRCT are diffuse hyperdense ground-glass attenuation and subpleural linear calcifications, often most predominant in the inferior and posterior portions of the lungs. Additionally, the medial aspects of the lungs appear to be more heavily involved than the lateral aspects. Ground-glass opacities, probably due to small calculi in the air space, are the most common finding in children and in patients with early-stage PAM. Magnetic resonance imaging
On magnetic resonance imaging (MRI), the calcific lesions usually show hypointensity or a signal void on T1- and T2-weighted images. Pulmonary function studies
Pulmonary function tests, arterial blood gases, ventilation perfusion relationships, and O2 diffusing capacity are normal in the initial stages of PAM. As the disease progresses, pulmonary function tests reveal typical features of a restrictive defect with reduced forced vital capacity (FVC) and elevated forced expiratory volume in FEV1/FVC. Treatment
To date, no treatment has been proven to effectively reverse or prevent the progression of PAM. Lung transplantation is an option for end stage disease, but is typically only recommended as a last resort when quality of life is significantly impaired.Etidronate is a bisphosphonate and can reduce the formation of calcium hydroxyapatite crystals. It has led to clinical and radiological improvements in few cases. Epidemiology
Since the disease was first described in 1918, over 500 case reports have appeared in the literature.
Nonbacterial thrombotic endocarditis (NBTE) is a form of endocarditis in which small sterile vegetations are deposited on the valve leaflets. Formerly known as marantic endocarditis, which comes from the Greek marantikos, meaning "wasting away". The term "marantic endocarditis" is still sometimes used to emphasize the association with a wasting state such as cancer. Risk factors
Marantic vegetations are often associated with previous rheumatic fever. Other risk factors include:
hypercoagulable states
malignant cancers, especially mucin-producing adenocarcinomas (most commonly associated with pancreatic adenocarcinomas)
systemic lupus erythematosus: Referred to as Libman-Sacks endocarditis
trauma (e.g., catheters)

Valve predilection
The disease affects the valves with following predilection: mitral valve > aortic valve > tricuspid valve > pulmonary valve

Histopathology
Grossly, vegetations form along lines of valve closure and are generally symmetric with a smooth or verrucoid (warty) texture. Histologically, lesions are composed of fibrin (eosinophilic) and platelets but, unlike bacterial etiologies, contain little evidence of PMNs, microorganisms or inflammation. Diagnosis
Due to the non-invasive nature of NBTE, clinical examination may or may not reveal a new murmur. An embolic stroke may be the first feature to suggest diagnosis of NBTE. An echocardiograph may be used to further assess for valvular lesions. References


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