Strep throat is a common bacterial infection of the throat and tonsils, medically known as streptococcal pharyngitis. The presence of white spots or patches on the tonsils is a key symptom. This visual symptom is a direct sign that the body’s immune system is actively fighting the bacterial invader. Understanding the nature of these spots and the infection that causes them is the first step toward seeking appropriate medical care.
What Causes the White Spots to Form
The white spots seen during a strep infection are called tonsillar exudates, a visible manifestation of the body’s localized inflammatory response. These spots are collections of pus, a semi-solid material that accumulates on the surface of the tonsils. Pus is primarily composed of dead white blood cells (neutrophils), dead tissue debris, and the remains of the bacteria. The tonsils have small pockets called crypts where the bacteria thrive and the immune battle concentrates. This intense fighting results in the accumulation of the white, sometimes yellowish, material that appears as spots or streaks across the inflamed, red tonsil tissue.
The Role of Group A Streptococcus Bacteria
The pathogen responsible for strep throat is Streptococcus pyogenes, commonly referred to as Group A Streptococcus (GAS). This bacterium adheres to the epithelial lining of the throat and tonsils. Once the GAS bacteria colonize the area, they trigger a rapid and significant immune response, leading to the intense inflammation and the formation of exudates. The infection is highly contagious and spreads primarily through respiratory droplets released when an infected person coughs, sneezes, or talks. GAS is a significant cause of pharyngitis, accounting for a large percentage of cases in school-aged children and adolescents.
How Strep Throat is Diagnosed and Treated
Because strep throat can lead to serious complications, accurate diagnosis and prompt treatment are necessary. A healthcare provider will typically use a throat swab to collect a sample from the back of the throat and tonsils for testing. The initial diagnostic tool is often the Rapid Antigen Detection Test (RADT), which detects GAS bacteria antigens within minutes. If the rapid test result is negative, especially in children, the provider may send the swab for a throat culture, a more sensitive test that takes up to two days for results.
A positive diagnosis requires a course of antibiotics, typically penicillin or amoxicillin, which are highly effective against GAS. Starting antibiotics quickly reduces the severity and duration of symptoms and prevents the spread of the infection. The full course of antibiotics, usually lasting for ten days, must be completed, even if symptoms improve quickly. Stopping treatment early can lead to a recurrence of the infection and increases the risk of developing serious conditions. These complications include rheumatic fever, which can cause permanent heart damage, and post-streptococcal glomerulonephritis, a kidney disorder.
Other Causes of White Spots on the Tonsils
While white spots often signal strep throat, they are not exclusively caused by the GAS bacterium. Several other conditions can cause similar-looking patches on the tonsils. Viral pharyngitis, a common cause of sore throats, can sometimes present with exudates, although a cough or runny nose usually accompanies these viral infections. Infectious mononucleosis, caused by the Epstein-Barr virus, is another condition that can produce thick, white-gray patches on the tonsils, often accompanied by extreme fatigue. Non-infectious causes also exist, such as tonsilloliths (tonsil stones), which are hardened deposits of debris, food particles, and bacteria trapped in the tonsil crypts. Because multiple causes share this visual symptom, only a medical professional using diagnostic tests can definitively confirm whether the white spots are due to strep throat.