surgery 210 for clinical officers

1. ML BRETHERTON
Bsc CM
PREMIUM SCHOOL OF HEALTH
SCIENCES
Surgical Infections Of The Skin And
Subcutaneous Tissues

2. SURGICAL INFECTIONS OF THE SKIN AND
SUBCUTANEOUS TISSUES
1.Applied anatomy and physiology of the skin
2.Inflammation and its natural history
3.Abscess, furuncle, carbuncle, cellulitis, erysipelas, pyomyositis, gas
gangrene, necrotizing fasciitis and septicaemia
Clinical presentation and managemen

3. Applied anatomy and physiology of the skin
 The integumentary system is the largest body organ and is composed of the skin, hair,
nails, and glands.
• The skin is further divided into three layers:
a) Epidermis
b) Dermis And
c) Subcutaneous tissue
EPDERMIS stratified squamous epithelium. The layered cells are avascular, dead,
keratinised, and cornfield. It is stratified into five layer (CLGSB)
• The epidermis, the thin avascular superficial layer of the skin, is made up of an outer
dead cornified portion that serves as a protective barrier and a deeper, living portion that
folds into the dermis. • Together these layers measure 0.05 to 0.1 mm in thickness. • The
epidermis regenerates with new cells every 28 days.

4. LAYERS OF THE EPIDERMIS
Layers (from deep to superficial):
• Stratum basale or germinatum – single row of cells attached to dermis; youngest cells
•Stratum spinosum – Made up of bundles of protein resist tension • Stratum granulosum –
layers of flattened keratinocytes producing keratin.
• Stratum lucidum layer that is present only on palms and soles
• Stratum corneum – horny cornified superficial layer
CELLS OF THE EPIDERMIS
• The two major types of epidermal cells are melanocytes (5%) and keratinocytes (90%). •
Melanocytes are contained in the deep, basal layer (stratum germinativum) of the
epidermis. • They contain melanin, a pigment that gives color to the skin and hair and
protects the body from damaging ultraviolet (UV) sunlight.

5.  Sunlight and hormones stimulate the melanosome (within the melanocyte) to increase the
production of melanin.
 • The wide range of skin color is caused by the amount of melanin produced; more
melanin results in darker skin color.
• Keratinocytes are synthesized from epidermal cells in the basal layer.
• As they mature (keratinize), they move to the surface, where they flatten and die to form
the outer skin layer (stratum corneum).
• Keratinocytes produce a fibrous protein, keratin, which is vital to the skin’s protective
barrier functionDermis • The dermis is the connective tissue below the epidermis. • Dermal
thickness varies from 1 to 4 mm. The dermis is very vascular.
10. • The dermis is divided into two layers, an upper thin papillary layer and a deeper,
thicker reticular layer. • The papillary layer is folded into ridges which extend into the upper
epidermal layer. • These exposed surface ridges form congenital patterns called fingerprints
and footprints.

8. DERMIS
Dermis is composed of
 Highly vascularised connective tissue like collagen and elastic fibres
 Sweat, oil glands and hair follicles
 Sensory receptors for heat, cold, touch, pressure and pain
 The dermis is the connective tissue below the epidermis. • Dermal thickness varies
from 1 to 4 mm. The dermis is very vascular.
 The dermis is divided into two layers, an upper thin papillary layer and a deeper, thicker
reticular layer.
• The papillary layer is folded into ridges which extend into the upper epidermal layer. •
These exposed surface ridges form congenital patterns called fingerprints and footprints.

9. HYPODERMIS /SUBCUTANEOUS TISSUE
• The subcutaneous tissue lies below the dermis and is not part of the skin.
• The subcutaneous tissue is often discussed with the skin because it attaches the skin to
underlying tissues such as muscle and bone.
• The subcutaneous tissue contains loose connective tissue and fat cells that provide
insulation.
• This layer also stores lipids, regulates temperature, and provides shock absorption.
SKIN APPENDAGES
Appendages of the skin include:
• Hair
• Nails
• Glands (Sebaceous, Apocrine, And Eccrine).

10. HAIR
Grows on most of the body except for the lips, the palms of the hands, and the soles of the feet
• The color of the hair is a result of heredity and is determined by the type and amount of melanin in
the hair shaft.
• Hair grows approximately 1 cm per month.
• On average 100 hairs are lost each day.
• When lost hair is not replaced, baldness results.
NAILS
• Nails grow from the matrix. The nail matrix is located at the proximal area of the nail plate. The
matrix is commonly called the lunula, which is the white crescent-shaped area visible through the
nail plate.
• The nail bed that is under the nail matrix and nail plate is normally pink and contains blood
vessels.
• Fingernails grow at a rate of 0.7 to 0.84 mm per week, with toenail growth 30% to 50% slower

14. GLANDS
Two major types of glands are associated with the skin: Sebaceous and
Sweat (apocrine and eccrine) glands.
• The sebaceous glands secrete sebum, which is emptied into the hair
follicles.
• Sebum prevents the skin and hair from becoming dry.
• Sebum is somewhat bacteriostatic and fungistatic and consists mainly of
lipids.

15.  These glands depend on sex hormones, particularly testosterone, to regulate
sebum secretion and production.
• Sebum secretion varies according to sex hormone levels.
• Sebaceous glands are present on all areas of the skin except the palms and the
soles.
• These glands are most abundant on the face, scalp, upper chest, and back.
• The apocrine sweat glands are located in the axillae, breast areolae, umbilical
and anogenital areas, external auditory canals, and eyelids.
• The eccrine sweat glands are widely distributed over the body, except in a few
areas, such as the lips.

18.  Inflammation and its natural history

19. Inflammation
 Inflammation is the protective response of the body to harmful
stimuli, such as pathogens, damaged cells, or irritants.
 The function of inflammation is to
 eliminate the initial cause of cell injury,
 clear out necrotic damaged tissues and
 initiate tissue repair

20. Inflammation
The five cardinal (classical) signs of inflammation are
 Heat (calor)
 Pain (dolor)
 Redness (rubor)
 Swelling (tumour)
 loss of function (functio laesa)

22. Inflammation
Inflammation can be classified as either acute or chronic.
 Acute inflammation - the initial response of the body to harmful
stimuli achieved by the increased movement of plasma and
leukocytes (especially granulocytes) from the blood into the
injured tissues. It is the first line of defense against injury.
 Chronic (prolonged) inflammation - leads to a progressive shift
in the type of cells present at the site of inflammation, such as
mononuclear cells, and is characterized by simultaneous
destruction and healing of the tissue from the inflammatory
process.

25. Inflammation
 Inflammation is not a synonym for infection.
 Infection is the interaction between the action of microbial
invasion and the reaction of the body's inflammatory response
—Inflammation on the other hand describes purely the body's
immunovascular response, whatever the cause may be.
 Words ending in the suffix -itis refers to inflammation,
sometimes these refer to infection as well e.g. the word
urethritis strictly means only “urethral inflammation”, but a
urethral infection because urethral microbial invasion is the
most common cause of urethritis.

26. e

27.  Abscess
 furuncle
 carbuncle
 cellulitis
 erysipelas
 pyomyositis
 gas gangrene, necrotizing fasciitis and septicaemia

28. Abscess

29. Abscess
 An abscess is a collection of pus that has built up within the tissue of
the body.
 Signs and symptoms of abscesses include redness, pain, warmth, and
swelling.
 The swelling may feel fluid-filled when pressed. The area of redness
often extends beyond the swelling.
 Carbuncles and boils are types of abscess that often involve hair
follicles, with carbuncles being larger.

30. Abscess
 They are usually caused by a bacterial infection. Often many
different types of bacteria are involved in a single infection.
 Diagnosis of a skin abscess is usually made based on what it
looks like, and is confirmed by cutting it open.
 Standard treatment for most skin or soft tissue abscesses is
cutting it open and drainage (I&D)
 There does not appear to be any benefit from also using
antibiotics for this type of abscess in most people who are
otherwise healthy

32. Abscess (Carbuncles, furuncles)
 A boil (or furuncle) is an infection of a hair follicle that has a
small collection of pus (called an abscess) under the skin.
 Usually single, a carbuncle is most likely to occur on a hairy
area of the body.
 A carbuncle is a red, swollen, and painful cluster of boils that
are connected to each other under the skin.

33. Abscess (Carbuncles, furuncles)
 Most carbuncles are caused by Staphylococcus aureus bacteria,
which inhabit the skin surface, throat, and nasal passages.
 These bacteria can cause infection by entering the skin through a
hair follicle, small scrape, or puncture, although sometimes there is
no obvious point of entry.

34. Signs and Symptoms
 The boils that collect to form carbuncles usually start as red,
painful swellings
 The carbuncle fills with pus and develops white or yellow tips that
weep, ooze, or crust.
 Over a period of several days, many untreated carbuncles rupture,
discharging a creamy white or pink fluid.
 Other symptoms include fever, fatigue, and a feeling of general
sickness.
 Swelling may occur in nearby tissue and lymph nodes, especially
lymph nodes in the neck, armpit, or groin.

35. Complications of carbuncles
 In rare cases, bacteria from a carbuncle can escape into the
bloodstream and cause serious complications,
 including sepsis
 infections in other parts of the body such as the lung, bones, joints,
heart, blood, and central nervous system.

39. Pyomyositis

40. Pyomyositis
 It is a bacterial infection of the skeletal muscles which results in a pus-
filled abscess.
 Its also known as tropical pyomyositis or myositis tropicans,
 most common in tropical areas.
 It is a purulent infection of skeletal muscle that arises from
hematogenous spread, usually with abscess formation.

43. Cellulitis

44. Cellulitis
 Cellulitis is a bacterial infection involving the inner layers of the
skin - the dermis and subcutaneous fat.
 Signs and symptoms include an area of redness which increases in
size over a few days.
 The borders of the area of redness are generally not sharp and the
skin may be swollen.
 The area of infection is usually painful.
 Lymphatic vessels may occasionally be involved, and the person
may have a fever and feel tired.

45. Cellulitis

47. Cellulitis
 The legs and face are the most common sites involved after a break
in the skin, but for the facial infections, a break in the skin
beforehand is not usually the case.
 The bacteria most commonly involved are streptococci and
Staphylococcus aureus.
 In contrast to cellulitis, erysipelas is a bacterial infection involving
the more superficial layers of the skin,

48. Cellulitis
 Diagnosis is usually based on the presenting signs and symptoms.
 Before making a diagnosis, more serious infections such as an
underlying bone infection or necrotizing fasciitis should be ruled out.
 Treatment is with antibiotics (cephalexin, amoxicillin, or cloxacillin).

49. Erysipelas

50. Erysipelas
 Erysipelas is an acute infection typically with a skin rash, usually
on any of the legs and toes, face, arms, and fingers.
 (Greek, “red skin”); also known as “holy fire”, and “St. Anthony’s
fire” in some countries,
 It is an infection of the upper dermis and superficial lymphatics,
usually caused by beta-hemolytic group A Streptococcus bacteria on
scratches or otherwise infected areas.
 Erysipelas is more superficial than cellulitis, and is typically more
raised and demarcated.

51. Erysipelas - Signs and symptoms
Affected individuals typically develop symptoms including
 high fevers,
 chills,
 fatigue,
 headaches,
 vomiting, and
 general illness within 48 hours of the initial infection.

52. Erysipelas - Signs and symptoms
 The erythematous skin lesion enlarges rapidly and has a sharply
demarcated, raised edge.
 It appears as a red, swollen, warm, and painful rash (similar in
consistency to an orange peel)
 More severe infections can result in vesicles (pox or insect bite-like
marks), blisters, and petechiae (small purple or red spots), with
possible skin necrosis.

53. Erysipelas - Signs and symptoms
 Lymph nodes may be swollen (lympadenitis), and lymphoedema
may occur.
 The infection may occur on any part of the skin, including the face,
arms, fingers, legs, and toes; it tends to favour the extremities.
 Fat tissue and facial areas, typically around the eyes, ears, and
cheeks, are most susceptible to infection.

54. Erysipelas - Cause
 Streptococcus pyogenes (also known as beta-hemolytic group A
streptococci), although non-group A streptococci can also be
the causative agent.
 It used to affect the face mostly, but today the legs are affected
most often.
 The rash is due to an exotoxin, not the Streptococcus bacteria,
and is found in areas where no symptoms are present; e.g., the
infection may be in the nasopharynx, but the rash is found
usually on the face and arms.

55. Erysipelas
 The infection can enter the skin through minor trauma, a small
scratch or abrasion insect bites, dog bites, athlete's foot, surgical
incisions and ulcers and often originate from streptococci bacteria
in the subject's own nasal passages.
 The infection then spreads, resulting in toxaemia.
 Erysipelas does not affect subcutaneous tissue.
 It does not release pus, only serum (serous fluid).
 Subcutaneous oedema may lead the physician to misdiagnose it as
cellulitis, but the style of the rash is much more well circumscribed
and sharply marginated than the rash of cellulitis.

56. Erysipelas

57. Erysipelas - Risk Factors
 This disease is most common among the elderly, infants, and
children.
 People with immune deficiency, diabetes, alcoholism, skin
ulceration, fungal infections, and impaired lymphatic drainage
(e.g., after mastectomy, pelvic surgery, bypass grafting).

58. Diagnosis
 This disease is diagnosed mainly by the appearance of well-
demarcated rash and inflammation.
 Blood cultures are unreliable for diagnosis of the disease
 Erysipelas must be differentiated from herpes zoster,
angioedema, contact dermatitis, and diffuse inflammatory
carcinoma of the breast.
 Erysipelas can be distinguished from cellulitis by its raised
advancing edges and sharp borders.

59. Erysipelas - Treatment
 Depending on the severity, treatment involves either oral or iv
antibiotics (penicillins, or erythromycin).

60. Septicaemia
 Septicaemia (sepsis, or blood poisoning) is a life-threatening condition
that arises when the body’s response to infection causes injury to its own
tissues and organs
 Common signs and symptoms include fever, tachycardia, tachypnoea,,
and confusion.
 Severe sepsis may cause poor organ function and or insufficient blood
flow (septic shock)
 Septic shock is low blood pressure due to sepsis that does not improve
after fluid replacement.
 Sepsis is usually treated with intravenous fluids and antibiotics

62. Pyemia
 Septicaemia caused by pyogenic microorganisms in the blood, often
resulting in the formation of multiple abscesses
 A form of septicaemia due to the presence of pus-forming organisms in
the blood, manifested by formation of multiple abscesses of a metastatic
nature
 a diseased state in which pyogenic bacteria are circulating in the blood,
characterized by the development of abscesses in various organ

63. Toxaemia
 blood poisoning resulting from the presence of toxins, as bacterial
toxins, in the blood
 A generic term for the presence of toxins in the blood
 An outdated medical term for Pre-eclampsia (used to be called
Toxaemia of Pregnancy)

64. Gas gangrene
 Gas gangrene is a bacterial infection that produces gas in tissues in
gangrene
 also known as and myonecrosis
 This deadly form of gangrene usually is caused by Clostridium
perfringens bacteria or any of many soil-borne anaerobic bacteria
which produce exotoxins.
 It is a medical emergency.

68. Gangrene
 Gangrene is a type of tissue death caused by a lack of blood supply

71. Gas Gangrene - Treatment
 Treatment is usually debridement and excision, with amputation
necessary in many cases.
 Although penicillin is effective against Clostridium perfringens,
antibiotics alone are not effective because they do not penetrate
ischaemic muscles sufficiently to be effective.

72. Debridement
 Debridement is the medical removal of dead, damaged, or infected
tissue to improve the healing potential of the remaining healthy tissue.
 It may be
 surgical
 mechanical
 chemical
 autolytic (self-digestion)
 by maggot therapy.

73. Debridement

74. Pyoderma

76. Necrotizing fasciitis
 Necrotizing fasciitis - a rapidly progressive inflammatory infection
of the fascia, with secondary necrosis of the subcutaneous tissues.
Necrotizing fasciitis moves along the fascial plane.
 Sometimes referred to as hemolytic streptococcal gangrene, acute
dermal gangrene, suppurative fasciitis.
 Fournier gangrene is a form of necrotizing fasciitis that is localized
to the scrotum and perineal area
 Symptoms include red or purple skin in the affected area, severe
pain, fever, and vomiting.
 The most commonly affected areas are the limbs and perineum

79. Fournier gangrene is defined as a polymicrobial necrotizing fasciitis of the perineal,
perianal, or genital areas.
Etiology & risk factors
•Initially described as idiopathic
•Now in more than 75% cases inciting cause in known
 •Necrotizing process commonly originates from infection in anorectum, urogenital tract
or skin of genitalia
Etiology
1.Ano-rectal causes –
 –infection in the perineal glands
 –Manifestation of colorectal injury, malignancy or diverticulitis
2.Uro-genital causes –
 –infection in the bulbourethral glands
 –urethral injury
 –Iatrogenic injury
 –Lower urinary tract infections

80. Causative Bacteria
•Polymicrobial infection
•Minimum of four isolates per case
•Most common aerobe – E. coli
•Most common anaerobes – Bacteroids
•Others – Streptococcus, Staphylococcus, MRSA – Methicillin Resistant
Staphylococcus aureus, Klebsiella Pseudomonas, Proteus & Clostridium.
Pathogenesis
•Bacteria act synergistically causing obliterative endarteritis & production of
various enzymes causing destruction
•There is imbalance between host immunity & virulence of organism

81. Mechanism of spread
Entry of bacteria (act through synergism)
 Fibrinoid coagulation of nutrient vessels
 Decreased locally blood supply to skin
 Decreased tissue oxygen tension Growth of anaerobes & microaerophilic
organisms
 Production of enzyme (Collagenase, Lecithinase, Hyaluronidase
 Digestion of fascial barrier Rapid spread of infection
Pathology
Pathognomonic findings on pathological evaluation of tissue are :-
•Necrosis of superficial & deep fascial planes
•Fibrinoid coagulation of the nutrient arterioles
•Polymorphonuclear cell infiltration
•Presence of micro organisms with in the involved tissues
•Air in the perineal tissue

82. Incidence
•Age – 30 – 60 years
•Sex – 10 times more common in males
•Social habits – More common in male homosexuals (more prone for
Rectal injury)
Clinical features
•Begins with insidious onset of pruritus and discomfort of external genitalia
•Prodromal symptoms of fever and lethargy, which may be present for 2-7
days before gangrene
•The hallmark of Fournier gangrene is out of proportion pain and
tenderness in the genitalia.
•Increasing genital pain and tenderness with progressive erythema of the
overlying skin
•Dusky appearance of the overlying skin; subcutaneous crepitation;
feculent odor

83. Differential diagnosis
•Balanitis
•Cellulitis
•Epididymitis
•Gas gangrene
•Compicated hernias
•Complicated hydrocele
•Necrotizing fasciitis
•Orchitis
•Testicular torsion

84. Investigations
 (CBC) Complete blood count
 Electrolytes
 BUN / Serum creatinine
 Blood Sugar
 ABG
 Blood and urine culture with sensitivity
 Coagulation profile for DIC
Imaging-
 Conventional radiography
 Ultrasonography
 C.T. Scanning
 MRI

85. Conventional radiography
•Consider where clinical findings are inconclusive
•Presence of gas in soft tissue

86. Ultrasonography
•Can be used to detect fluid or gas in soft tissue
•“Sonographic hallmark” – Presence of gas in scrotal tissue
•Excludes other conditions
•Testicular blood flow - N
•Limitations – Direct pressure on involved tissue causes inconvenience

87. Medical Treatment
1.Restoration of normal organ perfusion
2.Reduction of systemic toxicity
3.Broad spectrum antibiotics to cover anaerobes as well
(cipro+clinda+metro)
4.Vancomycin for MRSA
5.Tetanus prophylaxis
6.Irrigation with super oxidised water
7.Hyperbaric oxygen therapy
8.IV immunoglobulins to neutralize super antigen as streptotoxin A & B (as
adjuvant)
9.Antifungal – if required
10.Non – conventional
- Unprocessed honey – enzyme action

88. Surgical treatment
•Repeated aggressive debridement
•Preservation of testes (subcutaneous pocket from desiccation)
•Reconstruction after infection is over
•Fecal diversion
•Urinary diversion
•Vacuum assisted closure (VAC)
Complications
•ARF (Acute Respiratory Failure)
•ARDS (Acute Respiratory Disease Syndrome)
•Septicemia and gram negative shock
•Tetanus
•Death

90. Tropical Ulcer

91. Tropical ulcer
 Tropical ulcer is a chronic ulcerative skin lesion thought to be
caused by polymicrobial infection (a variety of
microorganisms)
 It is common in tropical climates.
 Ulcers occur on exposed parts of the body, primarily on
anterolateral aspect of the lower limbs and may erode muscles
and tendons, and sometimes, the bones.
 These lesions may frequently develop on preexisting
abrasions or sores sometimes beginning from a mere scratch

92. Tropical ulcer

93. Thank You