Lymphatic dysfunction Notes

NOTES NOTES LYMPHATIC DYSFUNCTION LYMPHEDEMA osms.it/lymphedema PATHOLOGY & CAUSES ▪ Lymphatic system becomes obstructed, causing protein-rich fluid buildup in tissues ▪ When flow is blocked, lymph gets backed up → drainage stops → fluid accumulates ▪ Inflammatory reaction: macrophages release inflammatory molecules → damages nearby cells → scarring, fibrosis (connective tissues thicken/scar tissue forms) → hardening CAUSES ▪ Filariasis: most common cause in lowincome countries ▫ Infection with nematode parasites (e.g. Wuchereria bancrofti) ▫ Nematode enters lymphatic system, causes fibrosis, creates a blockage ▪ Cancer, associated treatment: most common cause in high-income countries ▫ Removal of lymph nodes most common cancer treatment-related cause (e.g. axillary lymph nodes removed during mastectomy) ▪ Lymphedema praecox/primary lymphedema: congenital, results from lymphatic system not developing correctly < 35 years old ▪ Lymphedema tarda/primary lymphedema: > 35 years old, associated with genetic disorders (e.g. Turner syndrome) RISK FACTORS ▪ Older age, obesity, rheumatoid/psoriatic arthritis, Turner syndrome, smoking, cancer/ associated treatment (esp. breast cancer) Figure 13.1 Gross lymphedema of the left leg. STAGING ▪ Stage 0: latent stage. Damage to lymphatics but enough lymph still removed. Lymphedema not present ▪ Stage 1: spontaneously reversible. Tissue in pitting stage. Affected area normal/almost normal size in morning, progressively worsens throughout day ▪ Stage 2: spontaneously irreversible. Tissue spongy, non-pitting (bounces back when pressed). Fibrosis starts to develop → limbs harden, increase in size ▪ Stage 3: lymphostatic elephantiasis. Swelling irreversible, limbs large, hard from fibrosis OSMOSIS.ORG 95

COMPLICATIONS ▪ Recurrent cellulitis, limb swelling (esp. lower limbs), erythema, pain SIGNS & SYMPTOMS ▪ Chronic swelling , one limb larger than other ▪ Usually lower limbs; impairs movement ▪ Fatigue, fever, chills, weakness ▪ More likely to occur with superimposed bacterial/fungal skin infection ▪ Regional edema: begins as soft, pitting edema → progresses into chronic fibrosis without treatment DIAGNOSIS DIAGNOSTIC IMAGING Lymphoscintigraphy ▪ Nuclear imaging to assess lymphatic flow ▫ Radiotracer injected into affected limb → able to visualize dermal backflow, absent/delayed radiotracer movement, absent/delayed lymph node visualization TREATMENT ▪ No cure, no medication ▪ Depends on severity, limb fibrosis SURGERY ▪ Goal: improve drainage/reduce fluid load OTHER INTERVENTIONS ▪ Therapeutic exercises, self care ▪ Kinesio tape: applied to skin to channel lymph, reduce swelling ▪ Aquatic therapy Manual lymphatic drainage (MLD) ▪ Pneumatic pumps: substitute for MLD Compression ▪ Multilayer compression bandage: stop fluid accumulation ▪ Compression massages help lymph flow ▪ Compression garments MRI ▪ Shows severity, distribution of edema, lymphatic channels can be depicted after intracutaneous contrast injection MR venogram ▪ Helps differentiate lymphatic channels from superficial veins CT scan ▪ Assists in localization (subfascial, epifascial), characteristics (skin thickening, honeycomb pattern of edema) Ultrasound ▪ May be used to reveal blockages Figure 13.2 A plain X-ray of the forearm showing edema of the subcutaneous tissues. The subcutaneous fat shows characteristic streaky densities. 96 OSMOSIS.ORG