Coughing up a "stone" or a stone-like substance is a rare condition and should be taken seriously by the patient. The following are the etiologies when you cough up a “stone”:
Lithoptysis is an uncommon symptom that literally means to “cough up a stone”. First described by Aristotle in 300 B.C., lithoptysis is indicative of the presence of broncholiths tree., which are calcified peribronchial lymph nodes that erode into the bronchial tree. Broncholiths are usually composed of calcium phosphate or calcium carbonate. In the settings of a pulmonary infection, most commonly histoplasmosis, the lung parenchyma becomes alkaline, which enhances local precipitation of calcium phostate and carbonate. Rarely, patients with other fungal lung infections or silicosis may develop broncholiths. These calcifications typically form in the peribronchial lymph nodes and are usually asymptomatic unless one erodes in the airways lumen and is expected. In addition to lithoptysis, broncholithiasis may mead to cough, sputum production, hemoptysis, and recurrent episodes of post-obstructive pneumonia. Patients with lythoptysis may note gritty or sandy sputum or may actually cough up a small, stonelike object, which is pathognomonic for broncholithiasis. Rare complications of broncholithiasis include bronchoesphageal, aortoesophageal, aortotracheal, or bronchopleural fistula formation. Diagnosis of broncholithiasis is mainly clinical, especially if the patient saves the stone and presents it to the physician for analysis. Chest radiology, computed tomography, and bronchoscopy are useful for confirming the diagnosis and excluding complications. Treatment of patients with lithoptysis is generally supportive, although antibiotics are indicated for postobstructive pneumonia, and surgery may be needed if a complication is present.
Histoplasmosis, also known as "Darling disease" or "Cave disease" is very much similar with tubercolosis and could surpressed your body immune system. If symptoms of histoplasmosis infection happen, they will start within 3 to 17 days after exposure; the average is 12–14 days. Make sure to consult a lung specialist on the first three days to minimized the spread of such disease.
To avoid such illness, try not to inhale smokes. Cigarette once again is the leading cause of such symptom. Smoking cigarettes, even those second-hand smokes, is dangerous to health and can worsen your coughing up a stone symptom into a more deadly disease like lung cancer, emphysema and even heart and other lung diseases.
Here are other unusual symptoms: