Infectious mononucleosis (mono) is a highly contagious viral illness, most often caused by the Epstein-Barr Virus (EBV). Symptoms usually include extreme fatigue, fever, and a sore throat, which can sometimes be mistaken for strep throat. Patients often experience swollen lymph nodes in the neck and armpits, and sometimes a swollen spleen. Urgent care centers are equipped to perform the initial physical exam and necessary testing for mono detection.
Urgent Care’s Role in Mononucleosis Diagnosis
Urgent care centers offer an accessible option for patients experiencing symptoms consistent with mononucleosis. Because mono shares symptoms with other common illnesses like the flu or strep throat, the initial visit begins with a physical examination and medical history review. The provider checks for characteristic signs, including enlarged lymph nodes in the neck, armpits, and groin. They also gently press on the abdomen to check for an enlarged spleen or liver, which is a potential complication of the infection. If the physical examination and symptoms suggest mono, the provider proceeds with blood testing to confirm the diagnosis.
Specific Tests Used for Mono Detection
The most common and rapid test used in urgent care settings is the Monospot test, also known as the heterophile antibody test. This quick test detects specific antibodies the immune system produces in response to the Epstein-Barr virus. Results for this rapid blood test, which uses a small sample from a finger stick, are often available within minutes. A significant limitation of the Monospot test is its potential for a false-negative result, especially early in the illness.
The test may be negative for up to 25% of patients tested during the first week of symptoms because the heterophile antibodies have not yet reached detectable levels. If symptoms are highly suggestive of mono but the Monospot result is negative, the provider may order additional blood work or recommend repeat testing in seven to ten days. Alternative or confirmatory blood work may include a Complete Blood Count (CBC) with a differential, which can reveal an elevated percentage of atypical lymphocytes. The urgent care center may also send a blood sample to an outside lab for EBV-specific antibody testing. This serology panel is generally considered the gold standard for diagnosis and can distinguish between a current or past infection, but results take longer to process.
Post-Diagnosis Care and Management
If a mono diagnosis is confirmed, the standard treatment is supportive care, as the illness is caused by a virus and is not treated with antibiotics. This management focuses on rest, maintaining hydration, and using over-the-counter medications like acetaminophen or ibuprofen to manage fever, headache, and sore throat. Most patients begin to feel better within a few weeks, though significant fatigue can sometimes persist for a month or longer.
A major safety concern immediately following a diagnosis is the risk of splenic rupture, which is rare but potentially serious, occurring in less than one percent of cases. Due to the inflammation and enlargement of the spleen, patients must strictly avoid contact sports, heavy lifting, and any strenuous activity for several weeks. Even minor trauma to the abdomen can cause the spleen to rupture while it is enlarged. Guidelines typically recommend a minimum of three weeks of activity restriction, with some sources advising caution for up to eight weeks, especially for those involved in high-impact activities.
Patients must seek immediate emergency medical care if they experience severe or sudden pain in the upper left side of the abdomen, as this could signal a ruptured spleen. Other emergency signs include difficulty breathing, severe jaundice, or a significant decrease in blood pressure.