Infections are caused by attacks from bacteria, virus, mushroom, parasites, insects (tick, flies, lice and more) or prions. Disease occurs when such microorganisms release harmful substances (toxins or destructive enzymes). Some people are particularly vulnerable, such as wood congenital (primary) weakened immune system, other diseases that reduce resistance (secondary immunodeficiency) or when using am immunosuppressant drugs such as cortisone, DMARDS og biological drugs against rheumatic disease. People with chronic rheumatic disease may be more susceptible to infections than others. It also applies to the "Opportunistic infections"Which usually does not occur without the immune system being impaired due to immunosuppressive drugs or illness.
Fatigue, fever and/or new symptoms from the skin (redness, pus, discharge), respiratory tract (ears, sinuses, throat, lungs), gastrointestinal tract (abdominal pain, diarrhoea) and urinary tract (burning and frequent urination) may indicate infection. However, the symptoms of infection differ between children, most adults and the elderly. Young children may show blue-tinged skin and lips (cyanosis), abnormally rapid breathing and small dotted rashes (petechiae) (reference: van den Bruel A, 2010). Fever over 40 degrees in children is also suspect. Among elderly people, the course can be the same as among immunocompromised people, so that the symptoms can be striking new fatigue, reduced appetite, pallor, mental cloudiness and new night sweats, but little fever. Signs of infection are therefore not always obvious at first. Special attention needed to detect infections in exposed persons.
Medical history reflects typical symptoms (see above) and sym
Clinical examination can reveal starting points for infection such as damage to the skin, red eardrums, redness or pus in the throat/pharynx, mucus sounds or crepitations by auscultation of the lungs and assessment of the joints, back and nervous system.
Laboratory tests often show signs of inflammation with high CRP and lowering reaction (SR) in the blood. The number of white blood cells may be clearly elevated (neutrophils in the case of bacterial infection, lymphocytes in the case of viruses and eosinophils in the case of parasites). Cultivation from blood (blood cultures) can reveal the type of infection present if the organisms circulate in the blood (bacteremia, Sepsis). Urine samples reveal infection by an increased number of white blood cells, traces of blood and bacterial products (nitrite) when checked with a needle stick.
Imaging in case of infection in the sinuses and lungs is useful.
Other: In the case of infection in the central nervous system, such as meningitis, spinal fluid examinations (after lumbar puncture) important. Chronic diarrhea can be investigated by stool samples.
- Please read about tropical diseases in a separate chapter.
- Please read about opportunistic infections in separate chapter