A 43-year-old man being treated for tuberculosis developed purple blotches across his left lower leg, and several of those lesions began seeping fluid the color of orange soda. Doctors at the Datta Meghe Institute of Higher Education and Research in Wardha, India, reported the case in the journal IDCases, tracing the reaction to rifampicin, one of the drugs at the center of standard tuberculosis treatment worldwide.
From a Swollen Neck to a Rash on One Leg
The patient had recently been diagnosed with cervical tuberculous lymphadenitis, a form of TB that settles in the lymph nodes of the neck rather than the lungs. He was started on a standard anti-tubercular regimen.
Not long after treatment began, he returned reporting unusual purple patches on his left lower limb, with discharge coming from a few of them. On examination, his physicians found multiple reddish-brown lesions, several weeping an orange-colored serous fluid. The pattern looked like purpura, the medical term for bleeding into the skin that produces flat purple or reddish-brown discoloration that does not blanch under pressure.
Purpura in a patient on TB drugs is a genuine alarm bell. The best-known blood complication of rifampicin is immune destruction of platelets, a reaction documented in the British Medical Journal in 1970 and capable of progressing to dangerous bleeding if the drug is continued.
The Orange Clue Pointed Back to the Drug
Anyone who has taken rifampicin has been warned about the color. The drug is known for turning urine, sweat, and tears a reddish-orange, and for permanently staining soft contact lenses. What makes this case unusual is where the color showed up.
The authors' reading is that the orange discharge most likely represented rifampicin being excreted systemically into serous fluid that was escaping through a compromised skin barrier. In other words, the drug was leaking out of the damaged skin along with the fluid, and it brought its signature pigment with it. That explanation is the treating team's interpretation rather than a laboratory-confirmed finding. The report does not describe testing the discharge for rifampicin.
Clinically, though, the color functioned as a pointer. It tied a frightening skin finding directly to a specific drug at a moment when the differential diagnosis was wide open.
Ruling Out the Dangerous Look-Alikes
Before settling on the drug, the team ran a systemic evaluation and laboratory workup aimed at excluding two conditions that can look similar and behave far worse.
The first was thrombocytopenia, a drop in platelet count. The second was systemic vasculitis, inflammation of blood vessels that can damage the kidneys, nerves, and lungs. Both were excluded. With those off the table and a clear temporal link between starting the regimen and the onset of the lesions, the physicians diagnosed rifampicin-induced purpura.
Rifampicin was immediately pulled from the regimen, and the patient was started on systemic corticosteroids to dampen the immune response. The lesions stabilized, the orange discharge stopped, and the skin healed without further complications.
It is worth being precise about what this establishes. This is a single case, diagnosed on the strength of timing and exclusion rather than a formal drug rechallenge, which would have carried its own risk. The authors present it as an illustrative image intended to sharpen clinical suspicion, not as evidence of how often this happens.
Why It Matters in a Country Still Reporting More Than 10,000 TB Cases a Year
Tuberculosis is not a historical curiosity in the United States. CDC's 2025 provisional surveillance data show 10,260 TB cases reported nationally in 2025, a rate of 3.0 cases per 100,000 people, compared with 10,395 cases and a rate of 3.1 in 2024. Those figures reflect reports received by the National Tuberculosis Surveillance System as of February 12, 2026, and the agency has cautioned that they are preliminary and may change when final numbers are published. Even with the slight decline, the national totals remain above pre-pandemic levels.
Every one of those patients faces months of multidrug therapy, and rifampicin is the backbone of it. The drug arrived in the 1960s and transformed tuberculosis care, cutting treatment from a year or more down to roughly six months, which is why it sits alongside isoniazid, pyrazinamide, and ethambutol in the standard first-line regimen. Losing it from a regimen, as this patient did, is not a trivial adjustment.
Serious skin reactions to the drug are rare, and the report does not claim otherwise. Its point is narrower and more useful: clinicians treating TB should keep drug-induced purpura on the list when a patient on therapy turns up with new purple lesions, because early recognition is what prevents the reaction from progressing.
For patients, the practical takeaway is not to stop treatment on their own. Interrupting TB therapy has its own consequences, including the risk of drug resistance. Anyone on anti-tubercular drugs who develops a new rash, unexplained bruising, purple spots, or bleeding should contact their treating clinician or TB program promptly so the regimen can be evaluated and adjusted by the team managing their care. The full case report is available open access.
Key Questions Answered
What actually happened to this patient?
A 43-year-old man treated for a tuberculous lymph node infection in his neck developed purple purpuric lesions on his left lower leg, with orange-colored serous fluid discharging from several of them, after starting standard anti-tubercular therapy.
Why was the discharge orange?
The report's authors believe the color came from rifampicin itself being excreted into serous fluid leaking through damaged skin. The drug is well known for tinting urine, sweat, and tears reddish-orange.
How did doctors know it was the drug?
They excluded low platelet count and systemic vasculitis through laboratory and systemic evaluation, then relied on the close timing between starting the regimen and the onset of lesions. There was no drug rechallenge.
Is this a common side effect of rifampicin?
No. The authors describe rifampicin-induced purpura as a rare hypersensitivity reaction. A single case report cannot establish how frequently it occurs.
Should someone on TB drugs stop taking them if a rash appears?
No. Stopping TB treatment without medical guidance risks treatment failure and drug resistance. Anyone who develops a new rash, bruising, purple spots, or bleeding while on TB therapy should contact their treating clinician promptly.
