Procedures & Testing: What Might Happen When Your Child Is Sick
When your child has breathing trouble, ongoing symptoms, or unclear illness, your provider may recommend certain tests or procedures to help get answers. Here’s what they may include.
Common Tests
- Flu / RSV / COVID Test — nose swab to check for respiratory viruses
- Strep Test — a fast throat swab to check for strep throat
- Urine Test — used when fever has no obvious source
- Blood Test — checks for inflammation, infection, or dehydration
- Chest X-ray — looks at the lungs if there’s coughing or fast breathing
- Pulse Oximeter — a painless clip on the finger or toe to check oxygen levels (watch a video about at-home pulse oximetry)
Summary of Test Accuracy
Specificity (SP) = how well the test avoids false positives. Higher specificity means fewer “false alarms.”
Sensitivity (SE) = how well the test catches true positives. Higher sensitivity means fewer missed cases.
| Test | What It Checks | Sensitivity (SE) | Specificity (SP) | Notes for Parents |
|---|---|---|---|---|
| Rapid Strep Test (antigen) | Detects group A strep in the throat | ~85% | >95% | May miss some cases (false negatives); backup throat culture may be done if suspicion is high. |
| Throat Culture | Confirms strep or other bacteria | ~90–95% | >95% | More accurate than antigen tests; takes 1–2 days, but results are very reliable. |
| Rapid Flu Test (antigen) | Influenza A/B | ~50–70% | ~90–95% | Faster but less sensitive; may miss early or mild flu cases. Best used during flu season. |
| PCR for Respiratory Viruses | Detects viral genetic material; comes in many forms. Rapid flu tests are often combined with tests for RSV, and since the pandemic, SARS-CoV-2 has also been included in a single swab kit. | >95% | >98% | For a one-time illness, any of these swabs is appropriate; for repeated illnesses, more comprehensive panels can test for about a dozen viruses. |
| Urine Dipstick | Screens for UTI (leukocytes, nitrites) | ~75–85% | ~80–90% | Fast and helpful, but not definitive — needs culture for confirmation. |
| Urine Culture | Confirms UTI | >90% | >95% | Gold standard; takes 24–48 hrs to grow bacteria. |
| Blood Culture | Detects bloodstream infections | Variable (~65–85%) | >95% | Best when taken before antibiotics; sometimes negative even with illness. |
| CBC (Complete Blood Count), sometimes with CRP | General infection/inflammation signs | — | — | Not diagnostic by itself, but helps show trends (e.g., high WBC count). |
| Chest X-ray | Pneumonia, fluid, inflammation | ~85–90% | ~90% | Can miss very early infections or subtle lung problems. |
| Pulse Oximeter | Blood oxygen level | High, when used appropriately | High, when used appropriately | Not diagnostic, but alerts providers to possible breathing problems. |
| Bronchoscopy | Visualizes airways, samples mucus | High (visual exam) | High | Used when less invasive tests don’t give answers. May find structural or infection issues. |
| Sweat Chloride Test | Screens for cystic fibrosis | >95% | >95% | Standard for CF diagnosis; painless skin test. |
| COVID Antigen Test | Detects viral protein | ~60–85% | ~90–95% | Good when symptoms are present, but can miss early cases. |
| COVID PCR | Detects viral RNA | >95% | >98% | Gold standard — highly sensitive and specific. |
| RSV Antigen Test | Respiratory syncytial virus | ~80% | ~90–95% | PCR is more accurate but takes longer. |
| Allergy Skin Test | Reaction to allergens | ~90% (for inhalants) | ~50–80% | Can be affected by meds, skin sensitivity, or age. Not helpful during infection. |
| Allergy Blood Test | Sensitization to allergens | Lower than skin test | Better than skin tests | Blood tests can be positive in infancy, unlike skin tests, which are typically not positive until school age, even in the face of allergy. |
Common Procedures
Bronchodilator inhalation may be delivered by:
- Nebulizer treatment — delivers mist medication to open your child’s airways
- Inhaler with spacer — a quick-relief tool for wheezing or asthma-like symptoms
- Nasal suctioning — clears mucus in babies or very congested kids
Less Common, But Important Procedures
These are rarely needed but may be used if symptoms don’t improve, are severe, or don’t have a clear cause.
Bronchoscopy
A small camera is passed through the nose or mouth into the lungs (under sedation). It lets the doctor see the airways and collect samples.
Used for chronic cough, unusual infections, or airway blockage concerns.
Lung Ultrasound or CT Scan
Used if an X-ray doesn’t give clear answers — can help spot fluid around the lungs, abscesses, or structural issues.
Sweat Chloride Test
A painless skin test that checks for cystic fibrosis. It may be done if there are frequent lung infections or poor weight gain.
Allergy or Immunology Testing
May be considered if your child has ongoing wheezing or frequent colds that don’t follow normal patterns.
Sleep Study (Polysomnography)
A monitored overnight test to evaluate breathing, snoring, or oxygen drops during sleep.
What to Expect
Your provider should always explain:
- Why a procedure is recommended
- What your child may feel (e.g., asleep, numb, or just ticklish)
- Whether it can be done in the clinic, ER, or hospital
- How soon you’ll get results
You can always ask: