Why This Combination Demands Immediate Attention
The pairing of skin vasculitis and lung involvement is a major red flag because it signifies the disease is not localized; it is systemic and aggressive. The organs with the richest networks of small vessels are most at risk. After the lungs and skin, the same process can swiftly affect:
- The Kidneys: This is the most critical danger. Kidney involvement can be silent at first but can lead to rapid kidney failure if untreated. Urine may become foamy or cola-colored from blood and protein leakage.
- The Nerves: Causing numbness, tingling, or weakness.
- The Joints: Leading to arthritis-like pain.
- The Sinuses and Ears: In conditions like GPA, this can cause chronic sinus infections, nosebleeds, and even hearing loss.
Other Potential, But Still Serious, Causes
While systemic vasculitis is a primary concern, this symptom duo can also point to other life-threatening conditions:
- Severe Allergic Reaction (Anaphylaxis): Can cause hives (red patches) and rapid-onset breathing difficulty due to throat swelling. This is a medical emergency requiring immediate epinephrine.
- Blood Clotting Disorders: Certain conditions can cause both superficial skin bleeding (purpura) and life-threatening pulmonary emboli (blood clots in the lungs), leading to sudden shortness of breath.
- Severe Infections: Such as bacterial endocarditis (heart valve infection), which can shower tiny infected clots to both skin and lungs.
- Lupus Flare: Systemic Lupus Erythematosus can cause vasculitis rashes and a serious lung inflammation called pleurisy.
