Infectious mononucleosis, commonly known as mono, is a contagious disease primarily caused by the Epstein-Barr Virus (EBV). This viral illness is characterized by a classic triad of symptoms: extreme fatigue, fever, and a sore throat. While low blood pressure, or hypotension, is not considered a typical symptom of the infection itself, it can occur indirectly as a result of the body’s reaction to the virus or from certain complications.
How Mononucleosis Affects Blood Pressure Regulation
The systemic inflammation caused by the body’s immune response to the Epstein-Barr Virus can affect the circulatory system. This widespread inflammation may lead to vasodilation, which is the widening of blood vessels throughout the body. When blood vessels expand, the total resistance to blood flow decreases, which can result in a temporary or mild drop in blood pressure.
Fever is a common symptom of mononucleosis, and the body’s efforts to fight the infection can result in dehydration. Patients may also reduce their fluid intake due to a painful sore throat, which further contributes to fluid loss. A lower overall fluid volume in the bloodstream directly translates to reduced blood pressure.
Many patients with mononucleosis experience fatigue, leading to extended periods of rest or bed rest. This physical inactivity can result in deconditioning, which impairs the body’s natural ability to regulate blood pressure quickly. When a person stands up after lying down for a long time, they may experience orthostatic hypotension, a sudden drop in blood pressure that causes dizziness or lightheadedness.
Severe Complications That Cause Hypotension
While most cases of mononucleosis resolve without serious issues, rare complications can directly and severely impact the circulatory system, leading to hypotension. One such complication is myocarditis, which is inflammation of the heart muscle. Inflammation of the myocardium impairs the heart’s ability to pump blood effectively, lowering the cardiac output. A reduced cardiac output means less blood is pushed into the circulation, resulting in a drop in blood pressure.
Another serious, albeit rare, event is the rupture of an enlarged spleen, a condition that can cause life-threatening internal bleeding. Splenic rupture is a medical emergency that leads to a rapid loss of blood volume, causing hypovolemic shock and severe hypotension. Hypotension can also result from secondary complications like severe systemic infection or sepsis, where an overwhelming immune response causes extreme vasodilation and capillary leakage.
An extremely rare complication, adrenal insufficiency, can also lead to hypotension. The adrenal glands produce hormones, such as cortisol, that are necessary for maintaining blood pressure and fluid balance. EBV infection can, in rare instances, affect the function of these glands, leading to an inability to maintain adequate blood pressure, which may require immediate treatment with replacement steroids.
Monitoring and When to Seek Medical Attention
Monitoring your symptoms and overall physical state is important during recovery from mononucleosis. To manage mild, temporary hypotension often associated with fluid loss, focus on consistent fluid intake, even if the sore throat makes swallowing difficult. Slowly changing positions, especially when moving from lying down to standing, can help counteract the effects of orthostatic hypotension.
Warning Signs of Severe Hypotension
Specific warning signs may indicate that low blood pressure is becoming dangerous or is a symptom of a severe underlying complication. You should seek prompt medical attention if you experience extreme dizziness that causes fainting, confusion, or a rapid, weak heart rate. These are signs that not enough oxygen is reaching the brain and other vital organs due to severely low blood pressure.
Emergency Complications
Immediate emergency medical care is necessary if you develop symptoms that could signal a life-threatening complication. These include sharp, sudden pain in the upper left side of the abdomen, which may indicate a ruptured spleen, or chest pain and shortness of breath, which could suggest myocarditis. A persistent fever that is high or unmanageable, or hypotension that does not improve with rest and fluids, also warrants an urgent consultation with a healthcare provider.