Lists (numbered lists indicate frequency, bulleted lists are in no specific order)

Abdominal masses, malignant

  1. most common abdominal malignancy: Neuroblastoma
  2. Wilms tumor
  3. Hepatoblastoma
  4. (Most common abdominal tumors in teens: NHL, Rhabdo, germ cell tumors)

The most common renal mass is

Other causes of abdominal masses

Causes of pancreatic insufficiency in children

  1. Cystic fibrosis
  2. Schwachman-Diamond

Disorders are associated with skeletal anomalies and hematologic disease.

Phagocyte dysfunction, general

B-cell defects (Mnemonic: Breasts can make a girl too X-rated: B-cell defects

T-cell defects (WASH'D'M): T-cell defects

Most common form of pure red blood cell aplasia in children

  1. Transient erythroblastopenia of childhood (TEC)
  2. Diamond-Blackfan anemia
  3. other forms of pure red cell aplasia are rare

Causes of direct (conjugated) hyperbilirubinemia: A yellow MAOIST. (oops, politically incorrect) or a more loving one: SI Te AMO: Differential for Cong Hyperbili

GI Bleeding

Osteogenesis Imperfecta

Most common surgical condition in newborn period (1/700) : Pyloric stenosis

most common cause of chronic diarrhea in childhood: Diarrhea of Infancy, Chronic nonspecific aka Toddler's diarrhea

Vaginal Bleed - Prepubescent
Top 3 causes:
  scratching because of pinworm
  vaginal foreign body

Most common inheritable cause of thrombophilia (3-8% caucasians; 1% African American): Factor V Leiden deficiency, defect R506Q

Most common coagulopathy (1% population): von Willebrand disease


Bone pain

3 types of histiocytosis

  1. LCH (EHL) Dave 'Birbeck' on CD1a: bone pain, rash, draining ear, draining pee, bumps, pallor/bleed, pulmonary infiltrates
  3. malignant

Type I Histiocytosis: Langerhans cell histiocytosis

Most common pediatric malignancy (1/3 of all malignancies in children): Leukemia

What other diseases/syndromes have increased risk of ALL?

Sites of leukemia relapse

The leading cause of death from disease in children and adolescents: Leukemia

Platelet disorders

#1 clinical manifestation of early congenital syphilis: Periostitis, Usually affects long bones; Usually asymptomatic; May be painful

bone most often fractured during birth

  1. clavicle
  2. humerus

4 entities assoc with absent or hypoplastic radius

Most common cause of decreased active motion of the upper extremity in a newborn: clavicle fracture

Two most common causes of intrauterine growth retardation:

#1 cause of non-communicating hydrocephalus: aqueductal stenosis

Most common serious malformation of the posterior fossa: Arnold Chiari II malformation

Arnold Chiari Malformation

  1. ACM I: tonsil herniation only
  2. ACM II: tonsils and brainstem herniation + usually myelomeningocele
  3. ACM III: herniation of cerebellum
  4. ACM IV: severe hypoplasia of cerebellum without herniation

Most common hereditary neuromuscular disease (1/3600): Duchenne Muscular Dystrophy

Most common epilepsy syndrome in childhood: Benign Rolandic Epilepsy (10% of childhood seizure disorders)

Most common seizure disorder of childhood: febrile seizures

Most common seizure type in childhood: Generalized tonic clonic

Muscular dystrophies


  1. von-Gierke: G6Pase deficiency: severe fasting hypoglycemia, gout at puberty
  2. Pompe: alpha-glucosidase (acid maltase, lysosomal enzyme) deficiency: hypotonia, then heart failure
  3. Cori: glycogen debranching deficiency: presents like type 1
  4. Anderson: glycogen-branching enzyme deficiency: progressive liver cirrhosis
  5. McArdle: muscle phosphorylase deficiency: exercise intolerance

Most common malignancy in children: leukemia
Mostt common solid malignancy in children
: Brain tumor, 20% of all tumors

5 most common brain tumors in children: ABCPE

Most common posterior fossa tumors:

  1. cerebellar astrocytoma

  2. medulloblastoma

  3. brainstem glioma

Most common brain tumor in children < age 7

Mnemonic for PNET

Causes of congenital stridor

  1. laryngomalacia
  2. vocal cord paralysis
  3. congenital subglottic stenosis/web

Most common cause of chronic glomerulonephritis in older children and adults

Most common obstructive lesion, most common cause of hydronephrosis in childhood: UPJ obstruction

Ureteroceles are the most common cause of urinary retention in females

Vaginal Bleed - Prepubescent
Top 3 causes:
  scratching because of pinworm
  vaginal foreign body

The most common primary orbital malignancy in childhood. this tumor should be a consideration in any child between the ages of  7 and 8 who has a rapidly progressing unilateral proptosis.: Rhabdomyosarcoma

The most common metastatic lesion to the orbit in childhood: neuroblastoma

The most common organic acidemias: propionic acidemia, methylmalonic aciduria, isovaleric acidemia