Generalized WeaknessGeneralized Weakness in a Ten-month-old Infant in a Ten-month-old Infant

Andrew S. Johnson, MDPediatric Emergency Medicine

University of Utah

Andrew Johnson, MD

Case PresentationCase Presentation

• 10-month-old healthy female brought to pediatrician due to general weakness for twenty-four hours.– Increased Drooling– “Droopy Eyelids”– Difficulty latching onto breast– Poor suckle

• Dx- Otitis media and viral syndrome• Tx- Begun on amoxicillin

Andrew Johnson, MD

Case PresentationCase Presentation

• Returns to E.R. that evening with right arm weakness

• PMHx:– Term pregnancy without complications– Frequent middle ear infections– Recent URI in patient and sibling– No other medications or herbal supplements

Andrew Johnson, MD

Case PresentationCase Presentation

• History (cont.)– Immunizations current

– No recent travel or camping

– Recent home remodel and waterline construction near home

– No corn syrup or honey exposure

– ROS: “loose” stools

Andrew Johnson, MD

Case PresentationCase Presentation

• Physical Exam– Temp. 36.6 °C, P 147, R 34, O2 sat. 99%,

BP 126/73

– Weakness in hands (R>L)

– Poor head control

– Difficulty sitting

– Face symmetrical, Gag intact, 2+ DTRs

Andrew Johnson, MD

Case PresentationCase Presentation

• Laboratory– CBC, Electrolytes, Spinal fluid, Urinalysis

• WBC 13,000, CO2 17

– Blood, Urine, Stool, and CSF Cultures

• Radiographs– Computed tomography of the head without

contrast: Normal

Andrew Johnson, MD

Case PresentationCase Presentation

• Hospital Course– Admitted to Neurology Service– Progressive Hypotonia– Nasogastric tube placed for feedings– Loss of gag reflex– Loss of facial expressions– Ptosis

Andrew Johnson, MD

BotulismBotulism

• 3 distinct clinical infections– Wound– Food borne– Infantile

• Adult- compromised host

• Clostridium Botulinum (Baratii, Butyricum) • Gram + rod, obligate anaerobe – hardy

spores• Most potent toxin known to man

Andrew Johnson, MD

Case PresentationCase Presentation

• Hospital Course (cont.)– MRI of head: normal

– Diagnostic studies obtained

– Definitive treatment initiated

Andrew Johnson, MD

Infantile Botulism: Infantile Botulism: BackgroundBackground

• Van Ermengem – 19th Century

• Botulus - Sausage (Latin)

• First infant case reported in 1931

• Distinct clinical entity – 1976

Andrew Johnson, MD

Infantile Botulism: Infantile Botulism: PathophysiologyPathophysiology

• Toxin-infection versus ingestion• Lack of competitive intestinal flora• Neuroparalytic disease caused by heat-

labile toxin• Irreversibly binds to presynaptic nerve

endings of cranial and peripheral cholinergic nerves

• Blocks calcium dependent exocytosis of acetylcholine vesicles

Andrew Johnson, MD

Infantile Botulism:Infantile Botulism:EpidemiologyEpidemiology

• Reservoir: soil (surface of fruit and vegetables), marine life, birds, honey– ? Corn Syrup

• Seven toxin types (A-G)• 90% of cases types A and B

– Type A- West of the Mississippi River– Type B- East to West Distribution

• 85% Indeterminate source• Majority of U.S. cases are Infantile

Andrew Johnson, MD

Infantile BotulismInfantile BotulismRisk FactorsRisk Factors

• Breast feeding (controversial)

• Transition in feedings

• Spore density

• Local construction or family member working with soil

• Honey consumption (4-25%)

Andrew Johnson, MD

Infantile BotulismInfantile BotulismClinical PresentationClinical Presentation

• 95% of cases occur in the first 6 months of life (range: day of life 6 – 363)

• SIDS association• Descending neuromuscular blockade

– Cranial nerves– Trunk– Extremities– Diaphragm

Andrew Johnson, MD

Infantile BotulismInfantile BotulismClinical PresentationClinical Presentation

• Symptoms– Constipation (most common, 65-95%)– Lack of expression– Weak suck and prolonged feeding– Drooling– Floppiness

• Signs– Poor Head Control– Loss of Gag/Suck– Sluggish or nonreactive pupils– Hyptonia/Hyporeflexia– Diminished range of eye movements

Andrew Johnson, MD

Infantile Botulism:Infantile Botulism:Physical ExamPhysical Exam

• Autonomic findings (anticholinergic)– Labile blood pressure and heart rate

– Decreased anal sphincter tone

– Urinary retention

– Flushed skin

– Constipation

Andrew Johnson, MD

Infantile Botulism:Infantile Botulism:Differential DiagnosisDifferential Diagnosis

– Sepsis– Myasthenia gravis– Guillain-Barre syndrome (Miller-Fisher

variant)– Tick paralysis– Heavy metal/organophosphate poisoning– Werdnig-Hoffman disease– Poliomyelitis– Hypothyroidism

Andrew Johnson, MD

Infantile BotulismInfantile BotulismDiagnosisDiagnosis

• Requires isolation of the organism or toxin• Laboratory

– laboratories, including CSF, usually show no significant abnormalities

– Stool samples for toxin and culture• + for up to 4 months

• Electromyography– Characteristic BSAP (Brief, Small, Abundant motor

unit Potentials)– Specific but not sensitive

Andrew Johnson, MD

Infant BotulismInfant BotulismDiagnostic TestingDiagnostic Testing

• Among 309 persons with clinically diagnosed botulism reported to CDC from 1975 to 1988:– Stool cultures for C. botulinum: 51% +

– Serum botulinum toxin testing: 37% +

– Stool botulinum toxin testing: 23% +

• Overall, at least one of the above tests was positive for 65% of all patients

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Botulism Testing CentersBotulism Testing Centers

Andrew Johnson, MD

Infantile BotulismInfantile BotulismTreatmentTreatment

• SUPPORTIVE– Await growth of new nerve endings

• Botulinum antitoxin (not used in infants)– Trivalent equine product against types A,B, and E available from

CDC – Associated with anaphylaxis and serum sickness

• Antibiotics – may increase toxin production or enhance neuromuscular blockade

(aminoglycosides)• Botulinum Immunoglobulin (BIG) via CDC

– Binds free toxin, halts progression of disease, and shortens length of hospitalization

Andrew Johnson, MD

Infantile BotulismInfantile BotulismComplicationsComplications

• Hyponatremia

• Hypoxia

• Aspiration pneumonia

• Urinary tract infection

• Otitis media

Andrew Johnson, MD

Infantile BotulismInfantile BotulismSummarySummary

• Consider this uncommon neuroparalytic disease in infants in the first year of life with weakness or cranial nerve deficits

• Diagnosis is confirmed by culture or toxin identification at regional centers

• Supportive care is the mainstay of early treatment

• Administration of BIG will prevent progression of disease

Andrew Johnson, MD

Infantile BotulismInfantile BotulismCase Presentation - ResolutionCase Presentation - Resolution

• Stool sample demonstrated toxin• EMG was consistent with botulism• BIG was administered and clinical status

stabilized• Patient gradually recovered over two

weeks and was discharged to home once gag reflex and feeding abillity had returned to normal