Fever in children is one of the most frequent reasons for pediatric visits to clinics, emergency departments, and primary care. It is both common and complex — sometimes harmless, other times signaling serious underlying conditions. To help streamline diagnosis and decision-making, medical professionals can use the handy and memorable mnemonic “PASS GUUM” to recall the major infectious causes of fever in the pediatric population.
Let’s explore each component of PASS GUUM with medical depth, diagnostic clues, red flags, and parental guidance.
Introduction: The Pediatric Fever Dilemma
A child with a fever — especially a very young one — can cause alarm for both caregivers and physicians. Unlike adults, children have developing immune systems, atypical presentations, and are at higher risk of rapid deterioration.
Fever is defined as:
- Rectal temperature >38°C (100.4°F)
- Oral temperature >37.5°C (99.5°F)
- Axillary temperature >37.2°C (99°F)
While many cases are benign viral illnesses, distinguishing self-limiting fevers from serious bacterial infections is crucial.
Overview Table: PASS GUUM Mnemonic for Pediatric Fever
| Letter | Condition | Type of Infection |
|---|---|---|
| P | Pneumonia | Lower Respiratory Tract |
| A | Acute Otitis Media | Ear Infection |
| S | Scarlet Fever | Streptococcal (Toxin-mediated) |
| S | Sepsis | Systemic |
| G | Gastroenteritis | GI Tract |
| U | Upper Respiratory Infection | Viral/Bacterial |
| U | Urinary Tract Infection | Genitourinary |
| M | Meningitis, Measles, Mumps | CNS and Viral Exanthems |
P: Pneumonia
Pneumonia is a lower respiratory tract infection that can present subtly or severely in children.
Symptoms:
- High-grade fever
- Rapid or labored breathing
- Chest indrawing or grunting
- Cough
- Poor feeding or lethargy (especially in infants)
Causative Agents:
- <5 years: Respiratory Syncytial Virus (RSV), Influenza, Parainfluenza
- Bacterial causes: Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus
Diagnosis:
- Clinical signs + auscultation (crackles, decreased breath sounds)
- Chest X-ray
- Pulse oximetry
Treatment:
- Oral antibiotics (e.g., amoxicillin)
- Oxygen support if hypoxic
- Fluids and fever control
A: Acute Otitis Media (AOM)
Middle ear infections are frequent in children due to shorter eustachian tubes.
Symptoms:
- Ear pain
- Fever
- Tugging of ears
- Irritability or night-time crying
- Possible ear discharge (if perforated)
Causative Organisms:
- S. pneumoniae, H. influenzae, Moraxella catarrhalis
- Often preceded by a viral upper respiratory infection
Diagnosis:
- Otoscopy: Red, bulging tympanic membrane
- Pneumatic otoscopy: Reduced mobility of tympanic membrane
Treatment:
- Pain management: Paracetamol or ibuprofen
- Antibiotics for children <2 years or with severe illness
- Amoxicillin is first-line
S: Scarlet Fever
Scarlet fever is a toxin-mediated disease caused by Group A Streptococcus (Streptococcus pyogenes).
Symptoms:
- High fever with sore throat
- Strawberry tongue
- Sandpaper-like rash on the trunk
- Pastia’s lines (rash in skin folds)
- Desquamation in later stages
Diagnosis:
- Throat swab culture
- Rapid Antigen Detection Test (RADT)
- CBC: Elevated WBC, neutrophilia
Treatment:
- Oral Penicillin V or Amoxicillin for 10 days
- Antipyretics for fever
- Isolation (contagious)
S: Sepsis
Sepsis in children is a medical emergency and requires prompt recognition and treatment.
Symptoms:
- Fever or hypothermia
- Lethargy
- Tachycardia
- Poor feeding
- Hypotension
- Rash (petechiae, purpura)
High-Risk Age Groups:
- Neonates (<28 days)
- Immunocompromised children
- Children with chronic illnesses
Common Pathogens:
- Neonates: Group B Streptococcus, E. coli
- Older children: Streptococcus pneumoniae, Neisseria meningitidis
Workup:
- CBC, blood cultures
- Urinalysis, urine culture
- Lumbar puncture
- Chest X-ray, CRP, Procalcitonin
Treatment:
- Empirical IV antibiotics (e.g., ceftriaxone ± vancomycin)
- Fluid resuscitation
- ICU care if unstable
G: Gastroenteritis
This is a self-limiting infection of the gut but can lead to dehydration, especially in infants.
Symptoms:
- Fever
- Diarrhea (watery or bloody)
- Vomiting
- Abdominal cramps
- Signs of dehydration (sunken eyes, dry mouth)
Common Causes:
- Viruses: Rotavirus, Norovirus
- Bacteria: Salmonella, Shigella, Campylobacter
- Parasites: Giardia
Management:
- Oral rehydration solution (ORS)
- Zinc supplementation
- Continue breastfeeding
- Hospitalize if severe dehydration or persistent vomiting
U: Upper Respiratory Tract Infections (URTI)
Common cold and sore throat are usually viral but sometimes bacterial.
Symptoms:
- Fever
- Nasal congestion or runny nose
- Cough
- Sore throat
- Hoarseness
Most Common Viruses:
- Rhinovirus
- Adenovirus
- Influenza
- RSV
Treatment:
- Supportive (fluids, rest, nasal saline drops)
- Avoid unnecessary antibiotics
- Educate parents on expected duration (7–10 days)
U: Urinary Tract Infection (UTI)
UTIs in young children may present only with fever.
Symptoms:
- Fever without focus
- Vomiting
- Irritability
- Incontinence in toilet-trained children
- Foul-smelling urine
Risk Factors:
- Female gender
- Vesicoureteral reflux (VUR)
- Constipation
Diagnosis:
- Urine routine and microscopy
- Urine culture (midstream or catheter sample)
- Renal ultrasound if recurrent
Treatment:
- Oral antibiotics (cefixime, amoxicillin-clavulanate)
- Parenteral therapy for febrile infants
M: Meningitis / Measles / Mumps
This last component includes serious CNS and systemic viral infections.
Meningitis
Symptoms:
- Fever
- Neck stiffness
- Vomiting
- Photophobia
- Seizures or altered sensorium
Pathogens:
- Neisseria meningitidis, S. pneumoniae, H. influenzae
- Viral: Enteroviruses, HSV
Treatment:
- Urgent LP if no raised ICP
- IV antibiotics: Cefotaxime + vancomycin ± steroids
Measles
Symptoms:
- High fever
- Cough, coryza, conjunctivitis
- Koplik spots (white lesions in mouth)
- Maculopapular rash starting behind ears
Treatment:
- Supportive care
- Vitamin A supplementation
- Isolation to prevent spread
Mumps
Symptoms:
- Fever
- Painful swelling of parotid glands
- Earache, jaw pain
- Orchitis in boys
Treatment:
- Supportive care (analgesics, hydration)
- Avoid sour foods
- MMR vaccine for prevention
Diagnostic Flowchart: Evaluating Pediatric Fever
Initial Assessment
→ Check temperature, vitals, alertness→ Look for focus of infection
No Obvious Focus?
→ Urine test, chest X-ray, full blood work→ Rule out UTI, pneumonia, sepsis
With Obvious Focus (Cough, Ear Pain, Diarrhea)
→ Symptom-specific testing→ Treat accordingly
Toxic-Looking Child or Altered Consciousness
→ Immediate hospitalization→ Broad-spectrum antibiotics
→ Lumbar puncture if indicated
Red Flags in Pediatric Fever
- <3 months with fever
- Fever > 5 days
- Seizures or altered mental status
- Dehydration signs
- Petechial rash
- Refusal to feed or lethargy
Parental Guidance for Fever Management at Home
- Use accurate thermometers
- Give age-appropriate doses of paracetamol/ibuprofen
- Ensure hydration (ORS, breastmilk, fluids)
- Dress child in light clothing
- Don’t use alcohol rubs or ice baths
- Monitor behavior and alertness, not just temperature
FAQs: Pediatric Fever and PASS GUUM Mnemonic
Q1. What is the most common cause of fever in children?
Usually viral URTIs or gastroenteritis. Most resolve without complications.
Q2. When should a parent worry about a fever?
If the child is less than 3 months, has seizures, poor feeding, rash, or looks lethargic, seek help immediately.
Q3. Can fever cause brain damage in kids?
No, not usually. It’s the underlying illness, like meningitis, that poses a risk — not the fever itself.
Q4. What are the most dangerous causes of fever in kids?
Sepsis, meningitis, and pneumonia are potentially life-threatening if untreated.
Q5. How effective is the MMR vaccine in preventing measles and mumps?
Highly effective. Two doses provide >95% protection.
Conclusion: “PASS GUUM” — A Smart Way to Approach Pediatric Fever
The mnemonic PASS GUUM is a powerful clinical tool that helps medical students, residents, and practitioners remember the major causes of fever in children. By keeping a structured approach, clinicians can rapidly triage, investigate, and manage fevers — from mild infections to life-threatening emergencies.
Fever is a symptom, not a disease. The real skill lies in identifying what lies beneath — and PASS GUUM is the perfect first step in that diagnostic journey.
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