Infections that keep coming back have a reason.
Everyone catches a few colds a year. It is worth looking for a reason when infections come more often than before, hit the same place again and again, last longer, or need strong antibiotics. Very often the reason is one treatable thing, and high sugar tops the list.
In plain words.
The body’s defences work in layers: the skin and linings keep germs out, and white cells in the blood hunt down those that get in. Anything that weakens a layer lets infections return.
The commonest reason is diabetes, often not yet known or poorly controlled. High sugar slows white cells down and feeds germs, so boils, urine infections, fungal rashes and chest infections keep coming back.
Other causes that lower the defences: steroids, cancer treatment and some medicines for arthritis or after a transplant; HIV; kidney or liver disease; heavy drinking; poor nutrition; and, rarely, a body that makes too few antibodies from birth.
Often the problem is a weak spot in one place: a kidney stone, an enlarged prostate or a bladder that does not empty fully for urine infections; damaged airways (bronchiectasis) or smoking for chest infections; a blocked sinus; or germs carried in the nose that keep causing boils.
Repeated antibiotics without a test can breed germs that no longer respond to them. A culture taken during an infection, before the antibiotic, names the germ and the medicine that works.
The body’s guard and its weak spots
Skin and linings keep most germs out. The few that slip through are caught quickly by white cells patrolling the blood.
High sugar makes white cells slow and sticky, and feeds germs. Gaps open in the lining, germs get through, and the same infection comes back.
Find the reason and fix it: bring sugar down, treat a stone or a blocked sinus, review medicines, and add vaccines. The guard holds again.
Go to hospital now if
- Infection with confusion, drowsiness, fast breathing, or skin that is cold, blotchy or bluish: call 112. This may be sepsis, where an infection spreads into the blood.
- Infection with fainting, a racing heart, or passing very little urine: go to hospital now.
- Fever while on cancer treatment (chemotherapy), after the spleen has been removed, or on high-dose steroids: go to hospital now.
- Redness spreading fast from a wound or boil, with fever, or pain much worse than the skin looks: go to hospital now.
- Fever with a stiff neck and a bad headache, or a rash of spots that do not fade under a glass: call 112.
- Fever with pain in the back or side and vomiting, with a urine infection: go to hospital now. It may have reached the kidney.
Call 112 or go to the nearest emergency department. Ambulance: 108 (102 in some states).
See a doctor within a week or two if
- You have had three or more infections of one kind in a year
- You are very thirsty, pass a lot of urine, or are losing weight
- Infections keep needing strong or repeated antibiotics
- You have thrush in the mouth without a clear reason
- You take steroids or other medicines that lower the defences, and infections are frequent
- A child has repeated ear, chest or skin infections, or is not growing well
Tests that help.
Not everyone needs every test. He decides which ones are worth doing for you.
| Test | What it tells |
|---|---|
| Fasting sugar and HbA1c | Look for diabetes, the commonest reason, or show whether it is controlled. |
| Complete blood count (CBC) | Counts the white cells that fight infection. |
| Culture during an infection (urine, pus or phlegm) | Names the germ and the antibiotic that works, before treatment starts. |
| HIV test (with your consent), kidney and liver function | Look for conditions that weaken the defences. |
| Ultrasound or X-ray of the place that keeps getting infected | Finds a stone, a bladder that does not empty, a sinus block, or damaged airways. |
| Antibody levels (immunoglobulins) | Only if nothing else is found, to look for a rare problem with the immune system. |
Have it ready.
Tick them off as you gather them. The ticks stay on this phone only.
Online, or in person?
Do not keep leftover antibiotics or start them on your own at the first sign of an infection. It hides the germ from the test and breeds resistance. Adults with diabetes, lung, heart, kidney or liver disease are usually advised a yearly flu vaccine and a pneumonia (pneumococcal) vaccine; ask whether they suit you.
A video call can
- Look at the pattern of your infections and work out the likely reason
- Order the right tests, including a culture at the next infection
- Bring sugar under control, and review medicines that weaken the defences
- Plan prevention: vaccines, hygiene for boils, and steps to cut urine infections
Needs a visit in person
- Blood tests and cultures, at a laboratory or by home collection
- Scans of the kidneys, sinuses or chest
- An examination, or a specialist procedure, where needed
- Any sign in the red box: that is an emergency
Talk it through with Dr. Arya.
Bring your reports and medicines to a video consultation. He goes through them with you, in plain words, and says clearly if you need to be seen in person.
Book a video consultationDr. Prabhat Arya · MBBS, MD (Internal Medicine) · Delhi Medical Council Reg. No. DMC-83759
