4) Multifocal Eosinophilic Granuloma Flashcards
Types of MEG
- Porphyria
- Ascorbic acid deficiency
- Zinc deficiency
- Niacin deficiency
- Hypercorticism
- Adrenal cortical insufficiency
- Hyper/hypothyroidism
- Xanthomas
- Neurofibromas
- Tuberculosis sclerosis
- Venous insufficiency and related
- DM & related
DM & related MEG types
- Diabetic dermopathy
- Necrobiosis lipoidica diabeticorum
- Diabetic bullae
- Acanthosis nigricans
Porphyria
- 1:25,000 in US, 1:1 female to male, generally adults
- Deficiency or mutation in uroporphyrinogen decarboxylase (UROD)
- Hereditary 20% vs Sporadic 80%
- Blistering photosensitivity
- Elevated plasma and urine total porphyrins
Porphyria cutanea tarda (PCT)
- Most common type of cutaneous porphyria while hepatoerythropoietic porphyria (HEP) is very rare with only 40 documented cases
- Iron-related and generally presents in adulthood while
HEP can present in children or adults depending on the degree of UROD deficiency
PCT classifications
- Inherited or sporadic
- Approximately 20 and 80 percent of cases, respectively
- Based on the presence or absence of heterozygous UROD mutations
PCT leads to
- Excess of porphyrins which are transported from the liver to the skin
- Leads to cutaneous phototoxicity
Acquired susceptibility factors for porphyria
- Alcohol use
- Smoking
- Estrogen use
- Hepatitis C virus or HIV infection are common
- Hemochromatosis mutations
Typical features of porphyria
- Chronic blistering photosensitivity commonly on the backs of the hands and other sun-exposed areas
- Can lead to infection, bullae, increased skin fragility, scarring, hyper- and hypopigmentation
Porphyria lesions
- May be pruritic and/or painful depending on stage and degree of severity
- Delayed cutaneous reaction to sun exposure which may result in the patient not being aware that the exposure is causing
the skin lesions
Porphyria diagnosis
- First line testing with measurement of plasma or urinary total porphyrins before more extensive testing
- Biopsy is not necessary unless trying to rule out another condition
- Once Dx is made, it is appropriate to have family members tested for UROD and/or hereditary hemochromatosis
Porphyria DDx
- Other cutaneous porphyrias which may or may not blister
- Epidermolysis bullosa
- Pseudoporphyria
- Phototoxic drug reactions and eruptions
Porphyria treatment
- Phlebotomy or low-dose hydroxychloroquine
- Reduction of susceptibility factors
- Choice between phlebotomy and hydroxychloroquine depends on the degree of iron overload and other susceptibility factors
Ascorbic acid deficiency
- Vitamin C deficiency known as “Scurvy”
- Essential dietary nutrient in humans
Ascorbic acid deficiency characteristics
- Ecchymosis and bleeding gums, perifollicular hemorrhage, petechiae and coiled hairs
- Symptoms are due to impaired collagen synthesis and disordered connective tissue secondary to deficiency
Ascorbic acid deficiency occurence
- Mostly in severely malnourished individuals, drug and alcohol abusers, or those living in poverty or on diets devoid of fruits and vegetables
Ascorbic acid deficiency symptoms
- Generally occur when the plasma concentration of ascorbic acid is less than 0.2 mg/dL
- Most specific symptoms, as early as three months, are follicular hyperkeratosis and perifollicular hemorrhage, with petechiae and coiled hairs
Common symptoms associated with ascorbic acid deficiency
- Ecchymosis
- Gingivitis (with bleeding and receding gums and dental caries)
- Sjogren’s syndrome
- Arthralgias, edema, anemia, and impaired wound healing
Hemorrhagic skin lesions associated with ascorbic acid deficiency
- Initially flat but may coalesce and become palpable
- Especially on the lower extremities which may resemble a systemic vasculitis
Musculoskeletal pain associated with ascorbic acid deficiency
- May be severe
- Can be caused by hemorrhage into the muscles of periosteum
Generalized systemic responses of ascorbic acid deficiency
- Weakness
- Malaise
- Joint swelling, arthralgias
- Anorexia
- Depression
- Neuropathy
- Vasomotor instability
Ascorbic acid deficiency imaging
- Sclerotic and lucent metaphyseal bands with periosteal reaction
- Adjacent soft-tissue edema
Ascorbic acid deficiency diagnosis
- Clinically and usually related to a direct history of vitamin C deficiency
Ascorbic acid deficiency treatment
- Vitamin C supplementation and reversal of the conditions that led to the deficiency
- Adults are usually treated with 300 to 1000 mg daily for one month
- Children recommended doses are 100 mg ascorbic acid given three times daily for one week, then once daily for several weeks until the patient is fully recovered
Ascorbic acid deficiency symptom resolution
- Many of the constitutional symptoms improve within 24 hours of treatment
- Bruising and gingival bleeding resolve within a few weeks
Zinc deficiency
- Mild deficiency is characterized by impaired growth velocity
- Severe depletion leads to growth retardation
- Dermatologic changes occur primarily in the extremities or around body orifices
Zinc biological role
- Forming tight bonds with certain amino acids
- Structural role in proteins
Zinc deficiency in chronic diseases
- Malnutrition (elderly, alcoholism, etc.)
- Malabsorption syndromes (gastric bypass, TPN, etc.)
- Diabetics due to alteration in zinc metabolism
Clinical manifestations of zinc deficiency
- Delayed sexual maturation, impotence, hypogonadism, oligospermia
- Alopecia
- Dysgeusia (impaired taste)
- Immune dysfunction
- Night blindness
- Impaired wound healing and various skin lesions