What is disease characterized by?

Signs: These are objective features of a disease that are identifiable by the examining doctor. Signs require direct observation or measurement. A few common examples are:

- Increased pulse

- Elevated temperature

- Skin rash

- Swollen lymph glands

- Muscle weakness

Symptoms: These are subjective sensations or experiences that the patient feels and cannot always be observed by the doctor. They help in understanding how the disease process affects the patient's well being. Some examples of symptoms are:

- Fatigue

- Nausea and vomiting

- Headache

- Itchy eye

- Backache

- Dizziness

Investigations: Some diseases are diagnosed based on medical tests of body tissues, secretions or excretions. These investigations help to determine the cause, extent and complications of a disease. Some common investigations are:

- Blood tests

- X-ray

- Urine tests

- Ultrasound test

- ECG (Electrocardiogram)

- MRI scan (Magnetic Resonance Imaging)

Treatment: Treating the underlying disease process.