Cutaneous Mucinoses Flashcards

Question

Reticular erythematous mucinosis (REM) associations

Answer 1

Generally not related to systemic diseases Not associated with abnormal lab tests ``` Malignancies - haem, breast, lung, colon HIV Thyroid dysfunction Diabetes Idiopathic thrombocytopenic Purpura SLE ```

Answer 2

``` OCP Pregnancy Menses Heat, sweat X-ray therapy Role of sunlight is controversial ``` Family Hx

Answer 3

Epidermis normal Mucin in upper dermis Slight vascular dilatation Perivascular (sometimes perifollicular) T cell infiltrate, with variable deep extension DIF negative (rarely IgM, IgA, C3 at DEJ)

Answer 4

Tumid lupus - clinical and histo similarities, lack immune serological abnormalities, respond well to HCQ, resolve without residual lesions (tumid lupus without reticulated lesions on the midline are strongly photosensitive, higher positive DIF, higher recurrence rate, present with other lupus features) Seb derm - central chest, scale Pityriasis versicolor - central chest, scale Confluent and reticulated papillomatosis of Gougerot-Carteaud (CARP) - scale

Answer 5

Chronic Prolonged duration of untreated May clear spontaneously

Answer 6

First line HCQ 400mg daily - improvement/healing within 1-2 months Second line TCS Systemic steroid Topical calcineurin inhibitors I.e. tacrolimus, pimecrolimus Third line Phototherapy I.e. UVA1, UVB (potential for exacerbation, but successful results reported) PDL Other Oral antihistamines Tetracycline CSA

Answer 7

Non-pitting swelling/induration Upper part of body (neck, shoulders, upper back) - typically begin on posterior neck, spread to scalp, shoulders, upper back Spares hands and feet Erythema Peau d’orange appearance Symmetrical, diffuse Progressive Limited body mobility/movement restriction Subtypes - Diabetic - Non diabetic (idiopathic, with preceding febrile illness/post-strep, with monoclonal gammopathy/multiple myeloma, misc conditions I.e. HIV, internal malignancy, autoimmune disorder)

Answer 8

Diabetic (poorly controlled insulin-dependent) - slowly progressive, non-resolving Non diabetic - idiopathic - with preceding febrile illness/post-strep URTI (also influenza, measles, mumps, chickenpox, CMV, diphtheria, encephalitis, dental abscess) - acute onset, complete resolution 6 months-2 years - with monoclonal gammopathy/multiple myeloma - slowly progressive, non-resolving - misc conditions I.e. HIV, internal malignancy, autoimmune disorder (RA, primary biliary cirrhosis, sjogren syndrome, dermatomyositis)

Answer 9

Normal epidermis Thickened dermis Swollen collagen fibres separated by wide spaces Mucin Subcut fat replaced by coarse collagen fibres No fibroblast proliferation

Answer 10

``` Systemic sclerosis (has additional sclerodactyly, Raynaud phenomenon, nail fold capillary changes, positive serum autoantibodies) Dermatomyositis Other infiltrates - - Myxoedema (mucin) - Amyloidosis (amyloid) Lymphoedema Cellulitis ```

Answer 11

``` Serositis Myositis Parotitis Hepatosplenomegaly Ocular Cardiac Dysphasia Dysarthria ```

Answer 12

Post-infectious scleroedema - benign course, self-limiting, resolves spontaneously 6 months - 2 years Diabetes/monoclonal gammopathy associated scleroedema - chronic, little chance of remission

Answer 13

To detect underlying disorder Throat swab, ASOT - recent strep infection Fasting blood glucose, HBA1C - diabetic control Serum, urine protein electrophoresis and immunofixation - monoclonal gammopathy, multiple myeloma USS - evaluate skin thickness at baseline, after treatment MRI - extent of disease progression (better than USS for this purpose)

Answer 14

Difficult, limited success No effective treatment Some patients (but not all) diabetes patients improve with better glucose control First line - Treat underlying cause UVA1, PUVA, nb-UVB (for disabling manifestations) Physio MSK rehab (for motion/respiratory disability) Second line - Electron beam radiotherapy Extracorporeal photopheresis IVIg Third line (immunosuppressants) - CSA MTX TCS, ILCS, pred

Answer 15

Bilateral shins, dorsum feet Thickened and indurated skin Orange peel appearance/texture due to prominent hair follicles Overlying hyperhidrosis or hypertrichosis 4 variants - - diffuse non-pitting oedema - plaque type - nodular type - elephantiasis Hyperthyroidism esp Graves’ disease, sometimes Hashimoto’s thyroiditis Sometimes no past/present Hx of thyroid dysfunction

Answer 16

``` Hyperkeratosis Papillomatosis Acanthosis Follicular plugging Mid to lower dermis separation of collagen bundles by mucin Perivascular lymphocytic infiltrate Increase mast cells Normal/increased fibroblasts Reduced elastic fibres ```

Answer 17

LSC Hypertrophic lichen planus Obesity-associated lymphoedematous mucinosis (no thyroid disease)

Answer 18

Elephantiasis variant less likely to have remission | Entrapment of peroneal nerve by mucinous connective tissue —> foot drop, faulty dorsiflexion

Answer 19

Biopsy Anti-TSH antibodies - high TSH - low —> high thyroid hormone to stimulate more TSH production

Answer 20

General measures - Reduce weight Stop smoking Normalise thyroid function (though pretibial myxoedema can still develop after treatment started) First line - Medium to high potency TCS under occlusion ILCS Compression stockings/gradient pneumatic compression (improves lymphoedema) ``` Second/third line (only for elephantiasis variant) - Rituximab Extracorporeal plasmapheresis IVIg Octreotide +/- shave removal N.B relapse after skin graft ```

Answer 21

Skin coloured papules, nodules, plaques Trunk, upper extremities Accompany/antedate connective tissue disease I.e. LE (cutaneous lupus mucinosis, usually associated with SLE but may also be associated with DLE/SCLE), dermatomyositis, scleroderma Clinical course may/may not be related to the underlying connective tissue disease activity Path - abundant mucin throughout dermis, sometimes subcut fat, slight/moderate perivascular lymphocytic infiltrate, positive lupus band General measures - sunscreen First line treatment - TCS, ILCS, HCQ Resistant cases - Pred, oral tacrolimus

Answer 22

13 months - 15 years old Acute eruption of multiple papules, sometimes linear infiltrated plaques scalp, face, neck, abdomen, thighs Subcut nodules face, periarticular areas on limbs, periorbital swelling Systemic symptoms - fevers, arthralgias, weakness, muscle tenderness No paraproteinaemia/bone marrow plasmocytosis/thyroid dysfunction Spontaneous resolution few weeks - months Avoid aggressive therapy as heals spontaneously

Answer 23

Benign localised cutaneous dermal mucinosis No systemic manifestations Anecdotal associations - hypothyroidism, myxoedema, scleromyxoedema, REM, anti-TNF Rx Reactive lesion Trauma may act as a trigger Asymptomatic solitary skin coloured papule/nodule, sometimes with cystic appearance Anywhere except in proximity of the joints of the hands, wrists, feet Treatment - surgical excision Path - - Diffuse ill-defined dermal mucin - Spares subcut tissue - Normal/slight increase fibroblast (spindle-shaped cells) - No inflammation - No increased vascularity - No elastic fibres - Normal/hyperplastic epidermis, sometimes forming collarette DDx - angiomyxoma (benign >1cm, subcut involvement by mucin + increased vascularity)

Answer 24

Benign ganglion cyst of digits Translucent dome shaped soft/fluctuate nodule +/- visible semi transparent contents Dorsal skin/near distal interphalangeal joint Surface smooth or verrucous Clinical/radio graphic evidence of osteoarthritis Grooving of the nail may precede/associate the cyst by up to 6 months Antecedent trauma in minority of cases MRI can denote Connection of cyst to underlying joint 2 variants - Over joints - ganglion type derived from joint fluid and synovial cells Between interphalangeal joints - myxomatous type derived from dermal fibroblasts Histo - Large deposit mucin containing stellate fibroblasts Multiple clefts Vascular spaces Epidermis - atrophied centrally, acanthotic laterally Sometimes transepidermal elimination of mucin Treatment - No consistently successful treatment Excision (relapse not uncommon) Multiple needling/aspiration followed by ILCS/cryo/sclerosant/CO2 laser (favoured as a conservative alternative to excision)

Answer 25

Children, adults in 30s/40s Familial cases ? Genetic predisposition Acute/subacute eruption 1 or several sharply demarcated erythematous plaques with follicular prominence (more reassuring if solitary lesion on the head/neck) Alopecia Scaling Differentiation with MF-associated follicular mucinosis is difficult Histo - Mucin within follicular epithelium, sebaceous glands abusing keratinocytes to disconnect from each other Perifollicular infiltrate of lymphocytes, histiocytes, eosinophils Absence of epidermotropism/atypical lymphocytes (favour MF-associated follicular mucinosis) T cell gene rearrangement not always useful to exclude MF-associated follicular mucinosis Treatment- No specific Rx Consider wait and see - many cases heal spontaneously 2-24 months Topicals - TCS, topical calcineurin inhibitor, topical retinoids/bexarotene, imiquimod ILCS Systemic - Pred, isotretinoin, minocycline, dapsone, HCQ, interferon alpha-2b Physical - PDT, UVA1

Answer 26

Cyclic eruption of itchy urticaria-like papules/plaques Head/face/neck of middle-aged men Rosaceiform/seborrhoeic background skin Red macules persist for a few weeks as lesions resolve No follicular plugging No alopecia No systemic manifestations ``` DDx - Urticaria Seb derm Rosacea Tumid lupus ``` Histo - Mucin deposition within hair follicles Perivascular and perifollicular infiltrate of lymphocytes and eosinophils T-cell gene rearrangement polyclonal Treatment - Chronic Difficult to treat Systemic - HCQ, Dapsone