Pediatrics

Question 1

What metabolic diseases can cause macrocephaly?

Answer 1

Tay-Sachs

Maple syrup urine disease (defect in breakdown of 3 amino acids)

Question 2

At what age is H. influ B vaccine no longer necessary if previously unvaccinated?

Answer 2

5yo…unless asplenic

Question 3

A patient presents with recurrent viral and fungal infections and an abnormal face. What is likely going on? What else would likely be seen? How can it be treated?

Answer 3

DiGeorge syndrome (deletion of 22q11)

Thymic and parathyroid hypoplasia
Congenital heart disease
Tetany

Calcium, vitamin D
Thymic transplant, bone marrow transplant
Surgical correction of heart abnromalities
IVIG or prophylactic antibiotics

Question 4

A patient has persistent infections of Candida albicans (skin, mucous membrane, and nails). What is this? What else is commonly going on?

Answer 4

Chronic mucocutaneous candidiasis (T cell deficiency)

Often associated adrenal pathology

Question 5

A boy was doing really well, then turns six months old and now has had multiple bacterial infections. What is likely going on? How is it treated?

Answer 5

X-linked agammaglobulinemia…abnormal B-cell differentiation –> low B-cell and antibody levels

IVIG
Appropriate antibiotics
Supportive pulmonary care

Question 6

A patient has recurring pulmonary and GI infections. What could be going on? How is it treated?

Answer 6

IgA deficiency…decreased IgA with normal levels of other immunoglobulins

Prophylactic antibiotics
IVIG…with caution, small risk of anaphylaxis

Question 7

Patient has recurring pulmonary and GI infections that are found to always be caused by encapsulated bacteria (H. influ, strep pneumo/pyo, E. coli, Klebsiella, Salmonella). Normal spleen…no sickle cell disease. What could be going on? How is it treated?

Answer 7

Hyper IgM disease…defect in T-cell CD40 ligand –> poor interaction with B-cells, low IgG and IgA, and excessive IgM

IVIG, prophylactic antibiotics, bone marrow transplant

Question 8

A teenager starts to have recurrent respiratory and GI infections. What is likely going on? What will likely be found on studies? How is it treated?

Answer 8

Common variable immunodeficiency…autosomal disorder of B-cell differentiation –> low immunoglobulin levels

Poor response to vaccines
Decreased CD4:CD8 T-cell ratio

IVIG
Appropriate antibiotics

Question 9

A patient has common variable immunodeficiency. What is likely seen on family history? What has to be worried about?

Answer 9

Family history shows both men and women affected

Malignant neoplasms
Autoimmune disorders

Question 10

A very young patient has had recurrent infections of all different kinds. What is likely going on? How should it be treated?

Answer 10

Severe combined immunodeficiency disease (SCID)…absent T-cells and abnormal antibody function

IVIG, antibiotics
Bone marrow transplant
NO live or attenuated vaccines

Question 11

A young boy comes in with eczema and recurrent bacterial infections caused by encapsulated bacteria. CBC shows thrombocytopenia. What is likely going on? What is the treatment?

Answer 11

Wiskott-Aldrich syndrome…decreased IgM with normal/high other immunoglobulins

Splenectomy
Antibiotic prophylaxis
IVIG, bone marrow transplant

Question 12

A 3yo is brought in for uncoordinated movements and telangiectasia. What is likely going on? What is the patient at increased risk of? Treatment?

Answer 12

Ataxia-telangiectasia…autosomal recessive disorder causing cerebellar dysfunction, cutaneous telangiectasia, decreased WBCs and IgA

Recurrent pulmonary infections in a few years
Cancer is more likely in this patient

IVIG and prophylactic antibiotics might help…but unable to limit disease progression

Question 13

A patient comes in with recurrent bacterial and fungal infections that cause cutaneous, pulmonary, and perirectal abscess formation and chronic lymphadenopathy. What is likely going on? How can it be treated?

Answer 13

Chronic granulomatous disease…neutrophils cannot digest engulfed bacteria

Prophylactic antibiotics
gamma-Interferon
Corticosteroids
Bone marrow transplant

Question 14

A patient comes in with chronic dermatitis, recurrent skin abscesses, and pulmonary infections. What is likely going on? What else would likely be seen? How is it treated?

Answer 14

Hyper IgE disease (Job syndrome)…Defect in neutrophil chemotaxis, T-cell signaling, and overproduction of IgE –> increased eosinophils

Coarse facial hair
Retention of primary teeth

Prophylactic antibiotics
Skin hydration and emollient use

Question 15

An albino patient comes in with recurrent staph a, strep, gram-, and fungal infections. He has had abnormal behavior and is found to have abnormal platelets. What is going on? What is seen on a smear? How is it treated?

Answer 15

Chediac-Higashi syndrome…autosomal recessive dysfunction of neutrophils

Large granules seen in granulocytes on peripheral smear

Prophylactic antibiotics
Bone marrow transplant

Question 16

A patient’s umbilical cord stayed on for a really long time, and now he is having recurrent bacterial infections of the upper respiratory tract and skin. What is likely going on? What is abnormal? Treatment?

Answer 16

Leukocyte adhesion deficiency…neutrophils cannot leave circulation

Type 1: leukocyte integrins
Type 2: E-selectin…cognitive impairment

Prophylactic antibiotics
Type 1: bone marrow transplant
Type 2: fucose supplementation

Question 17

What do complement deficiencies put patients at increased risk of?

Answer 17

Autoimmune disorders

Question 18

What cardiac defects are associated with Turner syndrome? What else is associated with this syndrome?

Answer 18

Coarctation of the aorta and bicuspid aortic valve

Renal defects and craniofacial abnormalities

Question 19

What is the karyotype of Klinefelter syndrome?

Answer 19

47XXY

Question 20

What effect does XYY have? XXX?

Answer 20

XYY –> tall, acne, mild mental retardation

XXX –> mental retardation, menstrual abnormalities

Question 21

A child is born with a small mouth, rocker-bottom feet, and overlapping fingers on grasp. What is likely going on? What else should be looked for? What is the expected outcome?

Answer 21

Trisomy 18…Edward’s

Cardiac defects, GI abnormalities

Frequently fatal within first year

Question 22

On US, a baby is found to have cleft lip and palate, cardiac defects, and polydactyly. What is likely going on? What is the expected outcome?

Answer 22

Trisomy 13…Patau

Frequently fatal within first year

Question 23

When do most trisomies occur (from a genetics standpoint…not older women)?

Answer 23

Nondisjunction during meiosis of maternal germ cells

Question 24

What is the most common cause of mental retardation overall? What is the most common cause of familial mental retardation in men? What are typical features of those men?

Answer 24

Down Syndrome

Fragile X syndrome…high number of terminal CGG repeats

Prominent jaw, large ears, large testicles, hyperactivity

Question 25

A child is born with a small head and low birthweight and has a high-pitched cry. What is likely going on?

Answer 25

Cri du chat…deletion of the entire 5p chromosome arm

Question 26

A child has mental retardation, multiple cranial abnormalities, and seizures. What deletion syndrome can cause this?

Answer 26

Wolf-Hirschhorn…deletion of 4p16 to end of arm

Question 27

A young patient is obese and overeats. Also has decreased muscular tone, mental retardation, and small hands and feet. What is likely going on?

Answer 27

Prader-Willi…15q11-15q13 deletion of PATERNAL allele

Question 28

A young patient has puppet like movement, happy mood, and unprovoked laughter, mental retardation, and seizures. What is likely going on?

Answer 28

Angelman…15q11-15q13 deletion of MATERNAL allele

Question 29

A patient has “elfin facies”, mental retardation, cheerful/friendly personality, and supravalvular stenosis. What deletion syndrome would explain this?

Answer 29

Williams…1q11.23