SEARCH RESULTS FOR: Onychomycosis

Onychomycosis

Dermatophyte Onychomycosis: Pathogenesis and clinical findings Authors: Holly Zahary Loreman Reviewers: Mina Youakim Elise Hansen Shahab Marzoughi Jodi Hardin* * MD at time of publication Host Risk Factors Environmental Risk Factors Immuno- compromised ↓ Immune response to infection Older age Peripheral vascular disease Reduced blood circulation Diabetes Pre-existing nail dystrophy Previous nail trauma Integrity of nail unit is compromised Micro- traumatic pressure on nail Dark, warm shoe environment Optimal conditions for fugal growth Exposure to tinea pedis or onychomycosis Direct spread of infection to nail unit High blood sugar favoring infection Dermatophytes invade corneocytes on stratum corneum, the uppermost non- living layer of keratinized skin Compromise/breaking of hyponychial seal or cuticle (connection between hyponychium and nail plate) Proximal Subungual White Superficial Tinea infection (e.g. Tinea Pedis, Corporis, Capitis) Infection spreads to distal hyponychial space Dermatophytes colonize local tissue in nail plate and nail bed Dermatophytes feed on keratinized tissue General Symptoms (All Subtypes) Spongiosis (Intercellular edema) Acanthosis (Thickening of stratum spinosum layer of epidermis) Hyperkeratosis (Thickening of stratum corneum In effort to rid infection) Papillomatosis (Projections of dermal papillae) Secondary damage to nail matrix Loss of nail Keratinocytes produce an acute, low-grade inflammatory cytokine response Onychomycosis Dermatophytic infection of the nail bed Inflammation promotes ↑ fluid to tissues for ↑ immune cell delivery Widespread inflammation thickens parts of the epidermis in efforts to shed the infection Inflammation and epidermal hyperplasia (↑ growth of cells) influence local dermal papillae (group of cells just beneath the hair follicle) to proliferate and project above the skin Distal Subungual Superinfecting bacteria or other fungi proliferate beneath the compromised nail imparting a yellowish appearance Distal Subungual Subtype (Thick yellow nails, keratin and debris accumulate distally underneath nail plate) Dermatophytes invade the proximal end of the nail plate Dermatophytes penetrate through the cuticle to the newly forming nail plate moving distally Proximal Subungual Subtype (Whitish discolouration of nail plate that begins proximally and moves distally, indicative of immunosuppression) Fungi predominantly invade various areas of the superficial nail plate layers eventually joining together White Superficial Subtype (Chalky white scale that spreads slowly beneath nail plate, well-defined “white islands” that coalesce as disease progresses) The entirety of the nail plate is infected by the dermatophytes Widespread inflammation thickens the nail plate as well as beneath the nail (subungual hyperkeratosis) in efforts to shed the infection Total Dystrophic Subtype (End-stage nail disease, entire nail becomes thick and dystrophic) Local spread of infection Dermatophytes spread causing cracks in the skin deeper into toe Abnormal keratinization in hyponychium Keratin accumulates between nail plate and hyponychium Fissure (splits in the skin) Bacteria enters lymphatics and bloodstream Cellulitis Sepsis Onycholysis (nail plate separates from nail bed) Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published Mar 13, 2024 on www.thecalgaryguide.com Dermatophyte Onychomycosis: Pathogenesis and clinical findings Authors: Holly Zahary Loreman Reviewers: Mina Youakim Elise Hansen Shahab Marzoughi Jodi Hardin* * MD at time of publication Host Risk Factors Environmental Risk Factors Immuno- compromised ↓ Immune response to infection Older age Peripheral vascular disease Reduced blood circulation Diabetes Pre-existing nail dystrophy Previous nail trauma Integrity of nail unit is compromised Micro- traumatic pressure on nail Dark, warm shoe environment Optimal conditions for fugal growth Exposure to tinea pedis or onychomycosis Direct spread of infection to nail unit High blood sugar favoring infection Dermatophytes invade corneocytes on stratum corneum, the uppermost non-living layer of keratinized skin Compromise/breaking of hyponychial seal or cuticle (connection between hyponychium and nail plate) Proximal Subungual White Superficial Distal Subungual Superinfecting bacteria or other fungi proliferate beneath the compromised nail imparting a yellowish appearance Distal Subungual Subtype (Thick yellow nails, keratin and debris accumulate distally underneath nail plate) Infection spreads to distal hyponychial space Dermatophytes colonize local tissue in nail plate and nail bed Dermatophytes feed on keratinized tissue Keratinocytes produce an acute, low-grade inflammatory cytokine response Onychomycosis Dermatophytic infection of the nail bed Inflammation promotes ↑ fluid to tissues for ↑ immune cell delivery Widespread inflammation thickens parts of the epidermis in efforts to shed the infection Inflammation and epidermal hyperplasia (↑ growth of cells) influence local dermal papillae (group of cells just beneath the hair follicle) to proliferate and project above the skin General Symptoms (All Subtypes) Spongiosis (Intercellular edema) Acanthosis (Thickening of stratum spinosum layer of epidermis) Hyperkeratosis (Thickening of stratum corneum In effort to rid infection) Papillomatosis (Projections of dermal papillae) Secondary damage to nail matrix Loss of nail Tinea infection (e.g. Tinea Pedis, Corporis, Capitis) Dermatophytes invade the proximal end of the nail plate Dermatophytes penetrate through the cuticle to the newly forming nail plate moving distally Proximal Subungual Subtype (Whitish discolouration of nail plate that begins proximally and moves distally, indicative of immunosuppression) Fungi predominantly invade various areas of the superficial nail plate layers eventually joining together White Superficial Subtype (Chalky white scale that spreads slowly beneath nail plate, well-defined “white islands” that coalesce as disease progresses) The entirety of the nail plate is infected by the dermatophytes Widespread inflammation thickens the nail plate as well as beneath the nail (subungual hyperkeratosis) in efforts to shed the infection Total Dystrophic Subtype (End-stage nail disease, entire nail becomes thick and dystrophic) Dermatophytes spread deeper into toe Bacteria enters lymphatics and bloodstream Abnormal keratinization in hyponychium Keratin accumulates between nail plate and hyponychium Local spread of infection causing cracks in the skin Fissure (splits in the skin) Cellulitis Sepsis Onycholysis (nail plate separates from nail bed) Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published MONTH, DAY, YEAR on www.thecalgaryguide.com Dermatophyte Onychomycosis: Pathogenesis and clinical findings Authors: Holly Zahary Loreman Reviewers: Mina Youakim Elise Hansen Shahab Marzoughi Jodi Hardin* * MD at time of publication Host Risk Factors Environmental Risk Factors Immuno- Older compromised age ↓ Immune response to infection Peripheral vascular disease Reduced blood circulation Diabetes Pre-existing nail dystrophy Previous nail trauma Integrity of nail unit is compromised Micro- traumatic pressure on nail Dark, warm shoe environment Optimal conditions for fugal growth Exposure to tinea pedis or onychomycosis Direct spread of infection to nail unit High blood sugar favoring infection Dermatophytes invade corneocytes on stratum corneum, the uppermost non-living layer of keratinized skin Compromise/breaking of hyponychial seal or cuticle (connection between hyponychium and nail plate) Tinea infection (e.g. Tinea Pedis, Corporis, Capitis) Infection spreads to distal hyponychial space Dermatophytes colonize local tissue in nail plate and nail bed Dermatophytes feed on keratinized tissue Keratinocytes produce an acute, low-grade inflammatory cytokine response Onychomycosis Dermatophytic infection of the nail bed General Symptoms (All Subtypes) Spongiosis (Intercellular edema) Acanthosis (Thickening of stratum spinosum layer of epidermis) Papillomatosis (Projections of dermal papillae) Hyperkeratosis (Thickening of stratum corneum In effort to rid infection) Secondary damage to nail matrix Loss of nail Proximal Subungual White Superficial Distal Subungual Distal Subungual Subtype (Thick yellow nails, keratin and debris accumulate distally underneath nail plate) Proximal Subungual Subtype (Whitish discolouration of nail plate that begins proximally and moves distally, indicative of immunosuppression) White Superficial Subtype (Chalky white scale that spreads slowly beneath nail plate, well-defined “white islands” that coalesce as disease progresses) Total Dystrophic Subtype (End-stage nail disease, entire nail becomes thick and dystrophic) Local spread of infection causing cracks in the skin Dermatophytes spread deeper into toe Abnormal keratinization in hyponychium Keratin accumulates between nail plate and hyponychium Onycholysis (nail plate separates from nail bed) Fissure (splits in the skin) Bacteria enters lymphatics and bloodstream Cellulitis Sepsis Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Legend: Published MONTH, DAY, YEAR on www.thecalgaryguide.com Dermatophyte Onychomycosis: Pathogenesis and clinical findings Authors: Holly Zahary Loreman Reviewers: Mina Youakim Elise Hansen Shahab Marzoughi Jodi Hardin* * MD at time of publication Host Risk Factors Environmental Risk Factors Immuno- Older compromised age ↓ Immune response to infection Peripheral vascular disease Reduced blood circulation Diabetes Pre-existing nail dystrophy Previous nail trauma Integrity of nail unit is compromised Micro- traumatic pressure on nail Dark, warm shoe environment Optimal conditions for fugal growth Exposure to tinea pedis or onychomycosis Direct spread of infection to nail unit High blood sugar favoring infection Dermatophytes invade corneocytes on stratum corneum, the uppermost non-living layer of keratinized skin Compromise/breaking of hyponychial seal or cuticle (connection between hyponychium and nail plate) Tinea infection (e.g. Tinea Pedis, Corporis, Capitis) Infection spreads to distal hyponychial space Dermatophytes colonize local tissue in nail plate and nail bed Dermatophytes feed on keratinized tissue Keratinocytes produce an acute, low-grade inflammatory cytokine response Onychomycosis Dermatophytic infection of the nail bed Proximal Subungual White Superficial General Symptoms (All Subtypes) Spongiosis (Intercellular edema) Acanthosis (Thickening of stratum spinosum layer of epidermis) Papillomatosis (Projections of dermal papillae) Hyperkeratosis (Thickening of stratum corneum In effort to rid infection) Secondary damage to nail matrix Loss of nail Distal Subungual Distal Subungual Subtype (Thick yellow nails, keratin and debris accumulate distally underneath nail plate) Proximal Subungual Subtype (Whitish discolouration of nail plate that begins proximally and moves distally, indicative of immunosuppression) White Superficial Subtype (Chalky white scale that spreads slowly beneath nail plate, well- defined “white islands” that coalesce as disease progresses) Total Dystrophic Subtype (End-stage nail disease, entire nail becomes thick and dystrophic) Local spread of infection causing cracks in the skin Dermatophytes spread deeper into toe Abnormal keratinization in hyponychium Keratin accumulates between nail plate and hyponychium Onycholysis (nail plate separates from nail bed) Bacteria enters lymphatics and bloodstream Fissure (splits in the skin) Cellulitis Sepsis Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Legend: Published MONTH, DAY, YEAR on www.thecalgaryguide.com Dermatophyte Onychomycosis (Tinea Unguium): Pathogenesis, clinical findings, Authors: Holly Zahary Loreman Reviewers: Elise Hansen Name Name* * MD at time of publication and complications Host Risk Factors Environmental Risk Factors Immuno- compromised ↓ immune response to infection Older age Peripheral vascular disease Diabetes Pre-existing nail dystrophy Previous Nail Trauma Integrity of nail unit is compromised Micro-traumatic pressure on nail Dark, warm shoe environment Optimal conditions for fugal growth Exposure to tinea pedis or onychomycosis Direct spread of infection to nail unit Reduced blood circulation High blood sugar, favoring infection Tinea pedis infection (see ‘Tinea Capitis, Tinea Corporis, and Tinea Pedis’) Infection spreads to distal hyponychial space Dermatophytes colonize local tissue in nail plate and nail bed Dermatophytes feed on keratinized tissue Proximal Subungual White Superficial Dermatophytes invade corneocytes on stratum corneum, the uppermost non-living layer of keratinized skin Compromise/breaking of hyponychial seal or cuticle (connection between hyponychium and nail plate) Keratinocytes produce an acute, low-grade inflammatory cytokine response Onychomycosis (Tinea Unguium) (dermatophytic infection of the nail bed) Distal Subungual General Symptoms (All Subtypes) Spongiosis Intercellular edema Acanthosis Thickening of stratum spinosum layer of epidermis Papillomatosis Projections of dermal papillae Hyperkeratosis Thickening of stratum corneum In effort to rid infection Secondary damage to nail matrix Loss of nail Distal Subungual Subtype Thick yellow nails, keratin and debris accumulate distally underneath nail plate Proximal Subungual Subtype Whitish discolouration of nail plate that begins proximally and moves distally, indicative of immunosuppression White Superficial Subtype Chalky white scale that spreads slowly beneath nail plate, well-defined “white islands” that coalesce as disease progresses Total Dystrophic Subtype End-stage nail disease, entire nail becomes thick and dystrophic Local spread of infection causing cracks in the skin Dermatophytes spread deeper into toe Abnormal keratinization in hyponychium Keratin accumulates between nail plate and hyponychium Onycholysis (nail plate separates from nail bed) Tissue Damage Cellulitis Sepsis Bacteria enters lymphatics and bloodstream Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Legend: Published MONTH, DAY, YEAR on www.thecalgaryguide.com