Pediatric Zebras
{
Rene Y. McNall-Knapp, MD, FAAP
Pedatric Hematology/Oncology, OUHSC
Keep worst possible diagnosis (UGLY ZEBRA) in
mind
 Family, patient, caregivers partner in care
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Expected course of disease
May take more than one visit
 Bad things don’t get better on their own
 Stay humble
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Telling the Difference
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Day 1
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4 y.o. boy presents with back
and leg pain for 2-3 days
History – no fever, hurting
mostly at night, usually very
active
Physical – unremarkable,
scattered bruises of various ages
Labs/Imaging - ?
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Case study #1
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Visit 2
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History – pain
worsening, not walking,
lethargy, bruising, fever
PE – bruising, pallor,
lymphadenopathy
Labs/Imaging
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Case Study #1
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WBC 4.4K (80%
lymphs)
Hemoglobin 5.2 g/dL
Platelets 10K
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Leukemia – in this case ALL
ALL/AML – most common cancer in childhood
 Presenting symptoms, findings
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Anemia – pallor, fatigue
Thrombocytopenia – bruising, bleeding
Leukocytopenia – infections, thrush, fever
Adenopathy – mediastinal, peripheral
Splenomegaly
Bone pain
Leukemia cutis
Diagnosis
Started on
induction therapy
for standard risk
ALL
 On day 29 was in
remission
 Continues on
chemotherapy
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Treatment and Results
Cancer is #1 disease killer in children
 Cancer is diagnosed in 1:300 boys and 1:330
girls before 21
 Stage at diagnosis has dramatic effect on
prognosis (morbidity and mortality)
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75% cure for all children walking in door
Importance of identifying
zebras
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Imagine if you didn’t catch it on visit 2
Patient worsened and worsened over next 2 weeks
Presents to local ER
Codes due to severe anemia and infection
Revived but multisystem organ dysfunction and
disseminated Aspergillus
Must treat leukemia in face of all of this
Challenges of delay in
diagnosis
1st visit
 Almost 2 y.o. girl with complaint of vomiting for
last month
 No rhyme or reason to the vomiting
 PE – small, fluid behind TM, otherwise
unremarkable
 Labs/imaging
 Assessment and plan – otitis, amoxicillin, RTC 2
weeks for ear recheck
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Case #2
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2nd Visit
History – continues to
have daily vomiting,
also acting as if
hurting inactive,
losing milestones
PE – weight loss,
sleepy
Labs/Imaging –
Assessment/Plans -
Case #2
Presents to ER 2 weeks later because parents worried
she might have a parasite
 History – vomiting everything, lost 1/3 of her weight
 Physical – emaciated, lethargic
 Labs/Imaging – normal labs, US abdomen and Xray
normal
 Admitted to hospital for observation
 That night stopped breathing – Code Blue
 Revived and imaging done
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Case #2 – Imagine If
Brain Tumor (Specifically Medulloblastoma)
 2nd most common cancer in childhood
 Prognosis depends on type and stage of diagnosis,
surgical resection
 Presenting symptoms – common for posterior fossa
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Nausea/vomiting
Headache
Head tilt
Ataxia
Lethargy
Double vision
Diagnosis
Infants – macrocephaly, sunset eyes, loss of
milestones, wasting
 Seizures – not febrile seizures
 Abnormal eye movements or looking through
peripheral vision
 Delayed or precocious puberty
 Abnormal growth
 Other cranial nerve palsies – drooling, aspirating,
facial droop
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Other Symptoms of Brain
Tumors
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First – do no harm
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Least invasive/radioactive test you can do to reassure
yourself
Let the kid keep some of his own blood
Second – build rapport with family for close followup
 Third – act deliberately using history and physical as
your guide
 Hint – there are algorithms out there to help!
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Approaches to zebra
symptoms
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Hypertension – should test at least annually and at every
sick visit
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Varies by age and height
Renal tumors disease, adrenal tumors and disease, coarctation
of the aorta (arm > leg), others
W/U – H&P, UA, CMP, renal US
Horses – essential hypertension
Fever > 5 days
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101 F
Leukemia, Kawasaki, unusual infections
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W/U – H&P, CBC, appropriate cultures
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Horses – I don’t know what but Zithromax will make it better
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Red light zebra symptoms
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Eye – abnormal eye movements, proptosis,
white reflex
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Brain tumor, retinoblastoma, metastatic
disease, rhabdomyosarcoma, orbital cellulitis
W/U – urgent ophthalmology referral, MRI
brain/orbit
Horses – normal for baby, conjunctivitis
Adenopathy
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>1 cm all except inguinal (>1.5 cm) and
supraclavicular (any)
Leukemia, lymphoma, EBV, other infections,
abdominal malignancy (Virchow’s node)
W/U – CBC, CMP, uric acid, LDH, CXR,
response to antibiotics (if appropriate case),
biopsy
Horses – common infections
Warning – do not give steroids
Red light zebra symptoms
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Wheezing, shortness of breath
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Foreign body, mediastinal mass, vascular ring
W/U – H&P, CXR
Warning – again steroids!
Abdominal mass
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Renal disease, tumors, benign lesions, severe constipation
W/U – H&P, Xray or abdominal US
Red light zebra symptoms
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Bone or joint pain
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Infection, leukemia, sarcomas,
metastatic lesions
W/U – H&P, CBC, Xray entire
bone, consider bone scan
Horses – growing pains, injury
Soft tissue mass
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Sarcoma
W/U – image (MRI) then
excisional biopsy
Horses – lipoma, ganglion cyst
Red light zebra symptoms
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Poor growth – growth charts essential
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Delayed or precocious puberty
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Brain tumor, Turner’s syndrome, other syndromes
W/U – H&P, ?endocrinology referral, ?imaging
Horses – normal for patient
Brain tumor, Turner’s syndrome, other syndromes
W/U – H&P, ?endocrinology referral, ?imaging
Horses – normal for patient
Testicular mass
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Testicular cancer
W/U – H&P, testicular ultrasound
Signs to collect yourself