Metabolic disorders and food allergies Flashcards

1
Q

How is a food allergy different than an intolerance

A

an allergy is an adverse reaction to food ingestion mediated by IgE
Intolerance is difficulty digesting or metabolizing a food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Food allergy is the main reason for

A

Anaphylaxis presenting to the ER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are symptoms of a food intolerance

A

Gas, bloating, abdominal pain, and diarrhea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are Sx of a food allergy

A

Immediate* pruritis, urticaria, flushing, swelling of lips, face, throat, nausea, vomiting, cramping, diarrhea, wheezing, light headed, hypotension, syncope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How do you diagnose a food allergy

A

Take an amazing history! have them keep a food journal

They can do a 2 week trial elimination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What history is important when suspecting food allergy

A
Frequency of food eaten 
Quantity eaten 
Ingredients 
How the food is prepared 
GI vs Derm vs Respiratory Sx 
Time in between exposures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What labs can you get if you suspect a food allergy

A
IgE test (skin prick test or IgE immunoassay) 
but, think about the pre-test probability; all the things you could find that you now need to work up and treat that weren't even Sx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do you treat a food allergy

A

Epinephrine auto-injector (epi pen)- give GOOD instructions
Food avoidance
Allergist referral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is lactose intolerance

A

Intolerance to lactose containing food
MC in black, hispanic, asian, native american
Prevalence increases w/ age (not common <6 y/o)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What normally happens to lactose in the body

A

Lactase is found on microvilli of intestinal membrane.
It breaks down lactose to glucose and galactose
G&G are absorbed by the small intestine
Lactose that isnt absorbed goes into colon to be converted to fatty acid and hydrogen gas by colon bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does lactose intolerance occur

A

If you are missing lactase, you have a lactose malabsorption
All the lactose you eat goes into the small intestine and is converted to fatty acid and hydrogen gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Primary vs secondary causes of lactose intolerance are

A

Primary: race, development, congenital deficiency
Secondary: Bacteria overgrowth, infectious enteritis, mucosal injury (celiac, IBD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does lactose intolerance present

A
Abdominal pain 
Bloating 
flatulence 
diarrhea 
Borborygmi (really loud BS) 
Sx are affected by diet and vary in severity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do you diagnose lactose intolerance

A

Sx after lactose ingestion that resolve w/ avoidance

Lactose hydrogen breath test at baseline and q30 min x 3 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how do you treat lactose intolerance

A

Lactose free diet
Lactase enzyme helps a bit
Monitor calcium and vitamin D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is G6PD deficiency

A

X linked disorder where you don’t have G6PD, a RBC enzyme that generates NADPH and protects RBC from breakdown 2/2 oxidative stress

17
Q

G6PD deficiency is associated with

A

Hemolytic anemia

Nothing is protecting the RBC so they all lyse

18
Q

How does G6PD deficiency present

A

ASx until a trigger (med, food, acute illness/infx) causes hemolysis
Jaundice, pallor, dark urine, abdominal pain, back pain
Normochromic, normocytic anemia

19
Q

What are common findings on peripheral blood smear of G6PD deficiency

A
Bite cells 
Heinz bodies (denatured globin chains attached to RBC membrane)
20
Q

What does hemolytic anemia stimulate

A

Erythropoiesis; Reticulocytes can withstand oxidative stress better than adult RBC
Then you get a spontaneous resolution and reversal of anemia

21
Q

How do you treat G6PD deficiency

A

Avoid oxidative stress
Remove offending agent (antimalarials, sulfa drugs, abx, analgesics)
Hydration
Transfusion if anemia is severe

22
Q

What is Paget’s disease of bone

A

Unknown but genetic disorder causing increased bone turnover and overgrowth of bone. MC >55
Increased osteoclast activity= lytic lesion= increased osteoblast activity= disorganized bone formation and abnormal bones and enlarged skeletal deformity

23
Q

How does Paget’s disease of bone present

A

ASx w incidental discovery (elevated alk phos w/ isoenzymes indicating bone pathology)
Deep, aching pain worse at night and w/ weight bearing
Bowed tibias
Kyphosis
Chalkstick fractures w/ minimal trauma
increased hat size
HA

24
Q

What diagnostics should you get for Paget’s disease of bone

A

Bone turnover markers
Sr calcium (elevated)
Sr 25-OH vitamin D
Bone scintigraphy (tell you what areas of bone are actually involved)

25
Q

How do you treat Paget’s

A

ASx: monitor

Bisphosphanates (IV zolendronate has longest response rate before recurrence)

26
Q

Complications of Paget’s disease of bone are

A
Hypercalcemia 
Renal calculi 
high output HF 
Arthritis 
CN palsies 
Bone tumors
27
Q

What is rickets

A

Deficiency in calcium or phosphate leading to altered bone growth (soft, weak bones)
Decreased intake, Malabsorption, or Increased excretion of calcium, phosphate, or vitamin D

28
Q

Where are rickets bone deformities MC

A

Distal forearm
Knee
Costochondral junctions

29
Q

How does Rickets present

A

Bowing of weight bearing extremities
Skeletal fractures
Proximal myopathies

30
Q

What labs should you get for rickets

A
Alk Phos: high 
Sr. phosphorus: low 
Sr calcium: low-normal 
PTH: elevated in calcipenic rickets 
25 OH vitamin D
31
Q

What are some radiographic findings for rickets

A

Wide growth plate at long boned
Decreased radiopacity of long bones
If after growth plate closure: decreased cortical thickness, radiolucency

32
Q

How do you treat rickets

A

Treat underlying disorder

Vitamin D or calcium supplementation