Chapter 38 Infectious Disease Emergencies
FEVER
1 A 10-day-old, full-term male infant presents to the emergency department (ED) with a 1-day history of being fussy but consolable, slightly decreased oral intake, and a temperature of 38.5° C rectally. What is the risk for serious bacterial illness?
2 Which bacterial agents are of most concern in an infant < 28 days old presenting to the ED with a fever?
3 A 26-day-old infant presents to the ED with a 1-day history of fever up to 39° C rectally. What should your initial management include?
Perform a complete history (including prenatal history) and physical examination of the newborn.
Obtain laboratory studies, including a complete blood count (CBC) with differential and blood culture; urine obtained by catheterization or suprapubic aspiration for urinalysis, Gram stain, and culture; cerebrospinal fluid (CSF) for protein/glucose, cell count, Gram stain, and bacterial/viral cultures; chest radiograph if signs of respiratory distress (tachypnea, cyanosis, wheezing, retractions, grunting, nasal flaring, rales, rhonchi, or decreased breath sounds); and stool for heme testing and culture if bloody or watery stool is noted.
Admit patient to the hospital and administer parenteral antibiotics (ampicillin plus cefotaxime or gentamycin).
Consider IV acyclovir if neonatal herpes is suggested by history or physical examination.
5 A 6-week-old male infant presents to the ED with a temperature of 38.4° C. The infant appears nontoxic and is without an obvious source for the fever. How likely is this infant to have a bacterial infection?
6 What is the cause of a temperature of 38.0° C in infants age 1–3 months who present to the ED?
A published study of 422 such infants determined the following sources:
Nonbacterial gastroenteritis, 16.4%
Serious bacterial illness, 10.2% (growth of pathogen in cultures of blood, spinal fluid, urine, stool)
7 A 2-month-old presents with a temperature of 40.5° C and otherwise appears nontoxic. Do infants with hyperpyrexia have a higher risk of having a serious bacterial infection?
8 What is the most common cause of sepsis in newborns?
Early-onset (birth to 7 days) group B streptococcal (GBS) infections, which may be secondary to maternal obstetric complications, prematurity, or lack of prophylactic antibiotics prior to delivery. Late-onset GBS infection (7 days to 3 months) is uncommonly associated with these factors (Table 38-1).
Type of GBS | Usual Clinical Presentations | Comments |
---|---|---|
Early-onset GBS | Septicemia (25–40%) | 5–20% mortality |
Meningitis (5–15%) | ||
Respiratory illness (35–55%) | ||
Late-onset GBS | Meningitis (30–40%) | 2–6% mortality |
Bacteremia without focus (40–50%) | ||
Osteomyelitis/septic arthritis (5–10%) |
GBS = group B streptococcus.
9 Does the immature neutrophil (band) count help in distinguishing bacterial infections from viral infections in infants age 3–36 months presenting to the ED with a temperature > 39.0° C?
10 Has the introduction of the heptavalent pneumococcal conjugate vaccine (PCV7) affected the incidence of occult bacteremia?
OPHTHALMIC INFECTIONS
14 Distinguish between the presentation of preseptal and orbital cellulitis in children.
Feature | Preseptal Cellulitis | Orbital Cellulitis |
---|---|---|
Location | Infection of the eyelids anterior to the orbital septum | Infectious process posterior to the orbital septum involving the tissues within the orbit (eye, fat, muscles, optic nerve) |
Etiology | ||
Clinical presentation | ||
Fever/malaise | +/− | Usually + |
Orbital/eye pain | +/− | + |
Conjunctival hyperemia or swelling | + | + |
Upper-/lower-eyelid edema or erythema | + | + |
Signs of external trauma (insect bite, etc.) | + | + |
Fluctuance | +/− | +/− |
Photophobia | − | +/− |
Proptosis* | − | + |
Orbital pain | − | + |
Pain on eye movement | − | + |
Normal movement of eye* | + | − |
Visual loss or abnormal pupillary reactivity* | − | + (if severe) |
Signs of cavernous sinus thrombosis, meningitis, or intracranial abscess formation | − | + (if severe) |
+ indicates present, − indicates absent.
15 How should a patient with suspected orbital cellulitis be managed?
WBC count (often reveals leukocytosis with predominance of bands)
Blood cultures obtained before antibiotics
Orbital computed tomography (CT) with thin and coronal cuts, including frontal lobes
Lumbar puncture if meningeal signs are present (only after negative findings on CT of the head for signs of increased intracranial pressure)
Admission to the hospital for IV antibiotics (IV ceftriaxone or cefotaxime)
Consultation with ophthalmology, otorhinolaryngology, or infectious diseases, as necessary
16 What are the indications for hospital admission of infants and children who present with preseptal cellulitis?
17 For children discharged from the ED with the diagnosis of preseptal cellulitis, which antibiotics are best?
19 Distinguish between conjunctivitis caused by C. trachomatis and N. gonorrhoeae.
Features | Chlamydia trachomatis | Neisseria gonorrhoeae |
---|---|---|
Presentation | First 3 weeks of life | 24–48 hours after birth |
Distinctive clinical features | Initially serous then muco-purulent discharge Unilateral or bilateral | Acute onset of purulent conjunctival discharge, marked eyelid edema, and chemosis Septicemia, meningitis, or arthritis |
Potential complications | Self-limited Rarely conjunctival or corneal-scarring Potential development of upper and lower respiratory tract infections | Potential corneal ulceration and perforation |
Treatment | Oral erythromycin estolatesyrup for 2 weeks plustopical erythromycin four times a day | Parenteral ceftriaxone or cefotaxime, penicillin G,penicillin G topical |
20 A 5-year-old girl presents to the ED with “burning and itchy” eyes. She describes a sensation of “chalk in her eyes,” with some blurry vision. On physical examination, she has bilateral conjunctival hyperemia, chemosis, and ocular discharge, and has preauricular lymph nodes bilaterally. What is the differential diagnosis?
NECK INFECTIONS
22 What organisms are associated with deep neck infections (peritonsillar abscess, retropharyngeal abscess, and lateral pharyngeal abscess) in children?
EAR, NOSE, AND THROAT INFECTIONS
26 A 3-year-old boy with a history of mild to moderate eczema presents to the ED with ear pain and drainage. On physical examination, his tympanic membrane appears normal, although swelling of the ear canal makes it difficult to view the entire tympanic membrane. There is pain on movement of the tragus. There is no lateral displacement of the ear and no signs of mastoiditis. What is the likely diagnosis?
29 List the three major causes of exudative pharyngitis in children.
Exudate refers to white or gray debris on the tonsils or pharynx. Causes include:
30 A 7-year-old has fever, sore throat, tender anterior cervical lymph nodes, and lack of significant upper respiratory tract symptoms. Are these clinical features suggestive of GABHS pharyngitis?
32 How is the diagnosis of otitis media made?
Otitis media is diagnosed as an acute otitis media or otitis media with effusion. See Table 38-5.
33 Which pathogens are implicated in acute otitis media?
Streptococcus pneumoniae (35%)
Haemophilus influenzae, nontypeable (25%)
Viruses: Adenoviruses, coxsackie virus, measles virus, parainfluenza virus, rhinoviruses, respiratory syncytial virus
Others: Anaerobes; Chlamydia, Mycoplasma, and Staphylococcus spp., Mycobacterium tuberculosis agent
38 You decide to intubate the trachea of a young patient who presents with severe respiratory distress and stridor. On endotracheal intubation, purulent tracheal secretions are seen. What is the likely diagnosis?
39 What are the common causes of stomatitis? How can they be distinguished?
Buccal stomatitis may be due to infectious agents, Behçet’s syndrome, or trauma.
Gingivitis may be due to herpes simplex virus (HSV) or enteroviruses (coxsackie virus: hand-foot-mouth disease).
Gingivostomatitis may be due to an infectious agent: (HSV, Candida albicans) or Stevens-Johnson syndrome.
41 What are the typical organisms causing sinusitis?
The typical organisms associated with acute sinusitis include:
42 What criteria define sinusitis?
Acute bacterial sinusitis is an infection of the paranasal sinuses lasting less than 30 days that presents with either persistent or severe symptoms.
Persistent symptoms are those that last longer than 10–14, but less than 30, days and include nasal or postnasal discharge (of any quality), daytime cough (which may be worse at night), or both.
Severe symptoms include a temperature of at least 102°F and purulent nasal discharge present concurrently for at least 3–4 consecutive days in a child who seems ill.
44 When is imaging necessary in the diagnosis of acute bacterial sinusitis?
Wald ER: Clinical features, diagnosis, and evaluation of acute bacterial sinusitis in children, 2006: www.uptodate.com
45 When is CT useful in the diagnosis of sinusitis?
CT (Fig. 38-1) is helpful in children with complications of acute bacterial sinus infection or those with very persistent or recurrent infections that do not respond to medical management.
46 Describe the treatment of acute bacterial sinusitis.
1 For uncomplicated acute bacterial sinusitis of mild to moderate severity:
2 For children with acute bacterial sinusitis of at least moderate severity or who have received an antibiotic in the past 90 days or who attend day care:
3 Children with vomiting can be treated with one dose of IV ceftriaxone followed by oral antibiotics after vomiting has subsided.
Wald ER: Microbiology and treatment of acute bacterial sinusitis, 2006: www.uptodate.com
47 What is Pott’s puffy tumor?
Pott’s puffy tumor (Fig. 38-2) was first described by Sir Percivall Pott in 1760, and appears as a soft, fluctuant, painful forehead or scalp swelling usually associated with frontal sinusitis. Patients tend to be febrile and appear toxic. It is usually seen in children after 8 years of age when the frontal sinuses begin to develop. It represents osteomyelitis of the frontal bone with subsequent subperiosteal elevation. CT is essential for diagnosis and to evaluate other possible areas of spread. Successful treatment usually involves both antibiotics and surgical drainage.
CARDIAC INFECTIONS
50 What diagnostic test results in the ED support the suspicion of myocarditis?
Chest radiography can demonstrate cardiomegaly, interstitial pulmonary edema, or an engorged pulmonary venous pattern.
Electrocardiography may demonstrate mild to moderate PR interval prolongation, generalized low-voltage QRS complexes, ST-segment elevation or depression, decreased precordial voltages, high-grade atrioventricular block, and complex ventricular arrhythmias.
Echocardiography typically demonstrates global cardiac chamber enlargement with poorly contracting ventricles or atrioventricular valve regurgitation.
WBC count, erythrocyte sedimentation rate, and creatine kinase–MB fraction may be abnormal but are nonspecific.
51 What is the acute management of myocarditis in infants and children?
52 What are the common symptoms, signs, and laboratory findings in infants and children with infective endocarditis?
Symptoms | Signs | Laboratory Findings |
---|---|---|
Fever | Fever | Positive blood culture (75–100%) |
Malaise | Petechiae | Elevated erythrocyte sedimentation rate (75–100%) |
Anorexia/weight loss | Splenomegaly | Anemia (75–90%) |
Arthralgias | New or changed murmur | |
Less frequent | ||
Gastrointestinal symptoms | Embolic phenomenon | Hematuria (25–50%) |
Neurologic deficits | Heart failure | Positive rheumatoid factor (25–50%) |
Aseptic meningitis | Low complement level (5–40%) | |
Chest pain |
53 Differentiate among Osler nodes, Janeway lesions, and Roth spots.
Osler nodes are painful, red, nodular lesions seen most frequently on the pulp areas of the distal digits.
Janeway lesions are small, erythematous, nontender areas typically on the palms and soles.
56 What are the clinical manifestations and diagnostic findings associated with pericarditis?
Pericardial friction rub during deep inspiration with the patient kneeling or in the knee-chest position
If tamponade: tachycardia, peripheral vasoconstriction, decreased arterial pulse pressure, or pulsus paradoxus
Pericardial fluid analysis suggestive of infection
Increased size of cardiac shadow in the absence of pulmonary congestion on chest radiography (“water bottle heart”)
Electrocardiography: ST-segment elevations without reciprocal ST-segment depression, except in leads V1 and aVR; flattening or inversion of T waves (late), low-voltage QRS waves
Echocardiography: presence of pericardial fluid
Microbiological evaluation of the pericardial fluid by pericardiocentesis
Viral cultures, serologic tests, and molecular genetic techniques