Extrapulmonary Tuberculosis Presenting as an Infected Preauricular Sinus

Most people have never heard of a preauricular sinus, and for good reason. These are tiny, harmless pits that form just in front of the ear, a common leftover from how our faces develop before birth. For the vast majority of people who have them, these small openings cause no trouble at all. They sit quietly, doing nothing. However, because they are small tunnels leading into the skin, they can sometimes get blocked or infected. When that happens, the area swells, becomes painful, and may leak pus. In almost every case, doctors assume the culprit is a common bacteria like staph, the same kind of germ that causes a pimple or a minor skin infection. The treatment is usually straightforward: drain the infection, treat it with antibiotics, and if it keeps coming back, surgically remove the tiny tunnel.

But in a world where infectious diseases can hide in unexpected places, there is a rare possibility that a standard infection is actually something far more serious. Tuberculosis, a disease most people associate with the lungs, can sometimes settle in other parts of the body, including the skin and soft tissues near the ear. This is known as extrapulmonary tuberculosis. While it is well known that tuberculosis can affect the lungs, it is exceptionally rare for it to present as an infection in one of these tiny ear pits. Understanding this rare connection matters because treating a tuberculosis infection requires a completely different approach than treating a standard bacterial infection. If a doctor mistakes a tuberculosis infection for a common one, the patient will not get the right medicine, and the disease could spread or cause permanent damage.

A recent case report from Malaysia brings this rare scenario into focus, telling the story of an eighteen-year-old man who arrived at a hospital with a painful, swollen area in front of his left ear. He had been feeling unwell for five days, with the swelling growing, becoming tender to the touch, and leaking pus. He also had a fever that came and went. Just a week before these symptoms started, he had recovered from a COVID-19 infection. When the doctors examined him, they found a swollen, fluctuating lump on the left side of his face, right where a preauricular sinus would be, while the same spot on his right side was perfectly normal and dry. The patient had no other symptoms that usually point to tuberculosis, such as weight loss, night sweats, or a cough, and his chest X-ray showed clear lungs.

The medical team drained about three cubic centimeters of pus from the swelling to see what was causing the problem. When they looked at the fluid under a microscope, they found something that changed the entire course of treatment: the sample tested positive for acid-fast bacilli. This is a specific type of bacteria that includes the organism that causes tuberculosis. The presence of these bacteria in the pus, combined with the clear lungs, confirmed a diagnosis of extrapulmonary tuberculosis confined to the preauricular sinus. It was a rare instance where the disease had taken hold in this specific, unusual location without affecting the lungs.

Once the diagnosis was made, the treatment plan shifted entirely away from standard antibiotics. The patient was started on a specific four-drug regimen designed to fight tuberculosis, following the national guidelines for managing the disease in Malaysia. He took a combination of medicines for the first two months, followed by a slightly different combination for the next four months. The response was swift. By the one-month follow-up, his symptoms had completely disappeared. The swelling went down, the pain vanished, and the discharge stopped. Six months later, after the full course of medication was finished, the infection was considered resolved.

With the infection under control, the doctors moved to the final step to ensure the problem never returned. They performed a surgical procedure to remove the entire sinus tract, the tiny tunnel that had been the source of the trouble. During the operation, they carefully traced the path of the tract from the skin surface down into the tissue and removed it completely. The piece of tissue they removed was about one and a half centimeters long. This approach is crucial because simply draining the infection or taking medicine alone is often not enough to prevent the sinus from becoming infected again in the future. By waiting until the medication had cleared the active infection before performing the surgery, the team minimized the risk of complications and ensured a clean removal.

This case serves as a reminder that even in regions where tuberculosis is common, it can appear in the most unexpected forms. While most infections of the preauricular sinus are caused by ordinary bacteria, doctors must remain alert to the possibility of tuberculosis, especially when a patient has a history of recent illness or lives in an area where the disease is widespread. The successful outcome for this young man relied on a combination of two distinct steps: first, identifying the rare cause through careful testing, and second, using a coordinated approach of long-term medication followed by precise surgery. It highlights that when an infection behaves differently than expected, looking beyond the usual suspects can lead to the right treatment and a full recovery.