Pediatric Blood Disorders Flashcards
(33 cards)
ITP in children
Most common causes of thrombocytopenia in children (1/20,000)
- usually around ages 1-4 and precedes a viral infection
Usually acute but can be chronic
*most common viruses associated with it are Epstein-Barr Virus (EBV) and HIV
ITP pathogenesis in children
Target from antibodies against platelets remains undetermined.
Antibodies bound to platelets are recognized by the Fc receptor on splenic macrophages where they are destroyed
ITP clinical manifestations
Sudden onset of generalized petechiae and purpura
“Yesterday she was fine and now she is covered in purple dots/bruises”
- can show bleeding from gums, mucous membranes and profound thrombocytopenia
(< 10 x 10^9/L) - almost always says was sick 1-4 weeks ago with viral infection
- physical examination is normal outside of petechiae/ purpura
- rarely will show splenomegaly, lymphadenopathy, be one pain and pallor
( suggests possible leukemia as well)
Classification of ITP
1: no symptoms
2: mild symptoms: bruising/petechiae and minor epistaxia
3: moderate symptoms: severe skin/mucosal lesions, menorrhagia
4: severe symptoms: extreme bleeding episodes
Treatment of ITP
No cure
Mild treatment:
Just monitor and education, no drugs
Moderate-severe:
Treated with (0.8-1g/kg/day IVIG or prednisone 1st line of treatment
- monitor for 48 hrs
- once >20 x 10^9/L stop treatment
Hereditary spherocytosis in children
1/ 2000-5000 (most common in Northern European origin)
Defect in RBC skeletal proteins (usually an Anakryin or spectrin)
- RBCs are spherical shaped and burst easily/ cant fit through splenic cords/sinuses and are destroyed early by spleen macrophages
Clinical signs of hereditary spherocytosis
Anemia and jaundice
Splenomegaly
Recurrently hemolytic crises and gallstones in severe cases
- very dangerous if patient was recently affected with parvovirus B19 infection*
- results often in hematocrit <10% which is super deadly and can result in CV collapse
Possible other dangerous infections are HIV and hep B or C
Diagnosis of hereditary spherocytosis
Clinical symptoms hint at i t but the easiest way to diagnosis is a blood smear
- will show 750% increase of spherocytes and a low normal- low decrease of overall MCV.
- also show increased MCHC (>35g/dL)
- the gold standard with hereditary spherocytosis is the osmotic fragility test (will show cells bursting with slight hypotonic solutions)
Treatment of hereditary spherocytosis
Only “cure” or correction is splenectomy
Is also 75% a autosomal dominant trait with 25% arising de novo
- should monitor for hyperbilirubinemia in children that have parents with known hyper spherocytosis (would likely require transfusions and phototherapy)
G6PD in children
One of the PPP enzymes are defective, resulting in the inability to reduce Glutathione. This results in a increase chance of damage to RBCs via oxidative stress
- x-linked disease (more common in males)
G6PD clinical symptoms
Severe neonatal jaundice in the eyes out of nowhere cardinal sign
episodic acute hemolytic anemia (usually caused by drugs and rarely favs beans)
dark urine and/or hemoglobinuria
Back/abdominal pain
Hemolytic anemia
- often times will appear asymptomatic until triggered via some episode of oxidative stress*
- will show symptoms within 24-48 hrs after this event
G6PD diagnosis
Blood smear will show Bite cells and Heinz bodies golden standard
Drugs that cause oxidative stress to G6PD patients
Asprin (causes Reyes syndrome in children so shouldn’t be given anyways)
Sulfonamides (Sulfadrugs)
Rasburicase
Antimalarials (primaquine)
Fava beans (due to concentrations of divicine , isouramil, convicine)
G6PD treatment
Supportive therapy and blood transfusions
- No cure*
- note that males of Central African or Mediterranean descent should always be tested for this when born*
Diamond Blackfan Anemia (congenital hypoplastic anemia)
Rare, congenital bone marrow failure
Autosomal dominant disease that is usually diagnosed with 1st year of life
Can make them more susceptible to cancer in the future
Diamond-blackfan anemia clinical signs and diagnosis
50% have the following physical abnormalities
- short stature (<10% percentile)
- cleft palate and microcephaly (Most common 50%)
- cardiac/urogential abnormalities
- thenar eminance flattening
- super long thumb(looks like a normal finger)
super pale and blue eyes
* no or very poor radial pulse is a key sign*
Lab results Presents with macrocytic and normochromic RBCs, very reticulocytopenia and a very low MCV
DIamond- blackfan anemia treatment
Corticosteroids are the 1st line treatment
- however watch dose since corticosteroids are known to impair growth and neurocognative development. May chose to wait until 1 yr to start therapy because of this
- Hematopoietic Stem Cell transplantation is curative in some cases*
- best route is from sibling donors under age 9yrs
Fanconi anemia (FA)
Rare multisystem hereditary disorder that results in bone marrow failure
High chance of getting cancer and patients are highly sensitivity to alkylation get agents and radiation
Highrate of carrier (1/200) but very rare expression (1/200000)
Fanconi anemia symptoms
- produces a diagnostic triad*
- bone marrow failure
- congenital skeletal abnormalities
- elevated chromosome fragility (no teleomere)
Hearing loss Absent thumbs Microcephaly and microphthalmia Endocrine issues Hyperpigmentation
Treatment for Fanconi anemia
Bone marrow transplantation is curative
Di-George syndrome
22q11.2 micro deletion syndrome
- classic triad is conotruncal cardinal abnormalities, hypoplastic thymus and hypocalcemia*
- also almost always produces hypoparathyroidism and hypoplastic thymus as well
Di-George syndrome symptoms
Mild Skull deformities (cleft palate, prominent nose, narrow bases and ridges, retuned mandible, weak chin)
- 40-50% present with microcephaly
Hypocalcemia tetany/seizures is the most cardinal clinical sign
Signs of congenital heart disease
- ventricular septal defects and right aortic arch are the most common heart symptoms
Short stature
Hearing loss
Decreases motor tone and instability
Learning issues
Kawasaki disease (mucocutaneous lymph node syndrome)
- most common cause of acquired heart disease in children*
Idiopathic origin but hypothesized to be caused by bacterial/viral pathogens that turn on the defect
Ultimately will lead to vasculitis of coronary arteries and can cause MIs or aneurisms in coronary arteries
- ALWAYS PRESENTS WITH A RASH
90% of patients are less than 5 years old
- more common in males (1.5:1 ratio)
Possible causative agents for Kawasaki disease
Viral: measles, adenovirus, EBV
Bacteria: S. Aureus, step pyogenes, rickettsia, Lepto interrogans
Drug reactions: serum sickness and Stevens-Johnson syndrome
Rheumatologist disease: arthritis
Heavy metal toxicity
