Detailed answer

Dark spots, also known as hyperpigmentation, are commonly caused by factors such as sun exposure, hormonal changes, acne scars, and skin inflammation. Lung infections, on the other hand, primarily affect the respiratory system and do not directly contribute to the development of dark spots. However, it's important to note that certain medical conditions or medications used to treat lung infections may cause skin discoloration as a side effect. If you have concerns about dark spots or any changes in your skin, it's best to consult with a dermatologist for an accurate diagnosis and appropriate treatment.