What is Monge’s disease?

Monge's Disease: Chronic Mountain Sickness

Introduction

Monge's disease, also known as chronic mountain sickness (CMS), is a medical condition that affects individuals living at high altitudes, typically above 2,500 meters (8,200 feet). It is named after the Peruvian physician Carlos Monge-Medrano, who extensively studied the condition in the Andean population. Monge's disease is characterized by a range of physiological and clinical symptoms resulting from prolonged exposure to hypobaric hypoxia, or low oxygen levels, at high altitudes.

Pathophysiology

At high altitudes, the partial pressure of oxygen decreases due to lower atmospheric pressure, resulting in reduced oxygen availability for tissues and organs. Chronic exposure to hypobaric hypoxia triggers a series of physiological adaptations aimed at increasing oxygen delivery and utilization. However, in susceptible individuals, these adaptive mechanisms may become dysregulated, leading to the development of Monge's disease.

Symptoms

Monge's disease is characterized by a variety of symptoms, which can vary in severity and duration. Common symptoms include:

• Headache: Persistent or recurrent headache, often described as throbbing or pounding, is a hallmark symptom of Monge's disease. Headaches may be worsened by physical exertion or changes in altitude.

• Fatigue and Weakness: Individuals with Monge's disease often experience fatigue, lethargy, and weakness, even with minimal exertion. Reduced oxygen delivery to the muscles and tissues contributes to feelings of tiredness and reduced stamina.

• Shortness of Breath (Dyspnea): Difficulty breathing, especially during exertion or at rest, is a common symptom of Monge's disease. Dyspnea may be accompanied by rapid, shallow breathing or a sensation of air hunger.

• Cyanosis: Bluish discoloration of the skin, mucous membranes, or nail beds, known as cyanosis, may occur in individuals with severe hypoxemia. Cyanosis is a sign of tissue hypoxia and deoxygenated hemoglobin.

• Dizziness and Lightheadedness: Monge's disease can cause dizziness, lightheadedness, and vertigo, particularly when standing up or changing positions. Reduced oxygen supply to the brain impairs balance, coordination, and spatial orientation.

• Sleep Disturbances: Individuals with Monge's disease may experience sleep disturbances, such as insomnia, restless sleep, or frequent awakenings. Sleep-disordered breathing, including periodic breathing or nocturnal hypoxemia, may contribute to sleep disturbances.

• Cardiovascular Symptoms: Monge's disease can affect the cardiovascular system, leading to symptoms such as palpitations, chest pain, and elevated heart rate (tachycardia). Cardiac complications may include pulmonary hypertension, cor pulmonale, and right heart failure.

• Neurological Symptoms: Severe or prolonged hypoxemia can affect neurological function, leading to symptoms such as cognitive impairment, memory problems, and altered mental status. Neurological deficits may be reversible with oxygen therapy or descent to lower altitudes.

Diagnosis

The diagnosis of Monge's disease is based on clinical symptoms, medical history, and laboratory tests. Evaluation typically includes measurement of arterial blood gases (ABGs) to assess oxygenation status, as well as pulmonary function tests (PFTs) to evaluate lung function. Imaging studies, such as chest X-ray or echocardiography, may be performed to assess cardiac and pulmonary function.

Treatment and Management

The primary treatment for Monge's disease is oxygen therapy, which aims to alleviate hypoxemia and improve tissue oxygenation. Supplemental oxygen therapy may be administered via nasal cannula, face mask, or portable oxygen concentrator. In severe cases, hyperbaric oxygen therapy (HBOT) may be considered to increase oxygen delivery to tissues.

In addition to oxygen therapy, other treatment modalities may include medications to alleviate symptoms such as headaches (e.g., analgesics), manage pulmonary hypertension (e.g., vasodilators), or address underlying conditions (e.g., diuretics for fluid retention). Lifestyle modifications, such as avoiding alcohol and tobacco use, maintaining adequate hydration, and pacing physical activity, may also be recommended.

Prevention

Preventing Monge's disease involves gradual acclimatization to high altitudes, allowing the body time to adapt to reduced oxygen levels. Individuals planning to travel or reside at high altitudes should ascend gradually, avoid rapid altitude gains, and allow for adequate rest and hydration. Additionally, individuals with pre-existing medical conditions should consult with a healthcare provider before traveling to high altitudes to assess their risk and determine appropriate precautions.

Conclusion

Monge's disease, also known as chronic mountain sickness, is a medical condition characterized by symptoms resulting from chronic exposure to hypobaric hypoxia at high altitudes. Common symptoms include headache, fatigue, shortness of breath, cyanosis, dizziness, and sleep disturbances. Diagnosis is based on clinical evaluation and laboratory tests, and treatment typically involves oxygen therapy to alleviate hypoxemia and improve tissue oxygenation. Prevention strategies include gradual acclimatization to high altitudes and avoiding rapid altitude gains. Early recognition and management of Monge's disease are essential for optimizing patient outcomes and preventing complications associated with chronic hypoxia at high altitudes.