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Flashcards in Fever and Rash Deck (42):
1

 Papules

Small, solid, palpable lesions elevated above the plane of the skin

2

 Nodules

Masses located deeper within or below the skin

3

Vesicles and bullae

Blisters of differing size

4

Pustules

Small, palpable lesions filled with pus

5

Macule

Flat,nonpalpable, blanching

6

Purpura or petechiae

Nonblanching due to extravasation of blood

7

Erythema

 Hyperpigmented

 Blanching erythematous lesions due to vasodilatation

8

MACULOPAPULAR RASH Viral illness causes 

 Measles (Rubeola)

 Rubella (German measles)

 Erythema infectiosum (Parvovirus)

 Roseola (exanthema subitum, usually HHV-6)

Coxsackie 

9

Measles (Rubeola) characteristics 

 Paramyxoviridae – enveloped (-)ssRNA viruses

 Cough, Coryza, Conjunctivitis, posterior Cervical adenopathy, Koplik’s spots precede rash

 Rash

 Nonpruritic

 Cephalocaudal spread

 Face -> spreads downward

 Cetrifugalspread

 Face/neck/trunk -> extremities

10

Rubella

 Togaviridae- enveloped

(+)ssRNA

 “little red” – mild measles

 Rash also starts on face

 Petechial lesions on soft palate, NO Koplik’s spots

 Fever,lymphadenopathy

11

Parvovirus B19

 Parvoviridae,unenvelopedssDNA

 Erythema infectiosum,“5th disease”- school age children

 Clinical manifestations

 Viral syndrome=Fever,malaise,GI upset, lymphadenopathy

 Rash= “slapped cheek” with relative perioral pallor

 Some have secondary diffuse lacy reticular rash 

12

Parvo B19 associations 

 Infects erythroid precursors

 Reticulocytopenia: Severe – pure red cell aplasia

 HIV patients, Hemoglobinopathies (SCD, thalassemia)

 Acute polyarthritis in adults

 Congenital infectionHydrops fetalis

13

 Roseola

 HHV-6 and HHV-7

 Childhood illness

High fever prior to rash

 Rash starts on face or trunk

14

 Syphilis primary sx 

 Spirochete,Treponemapallidum

 Varied skin manifestations

 Primary

Chancre

Site of inoculation

Oropharynx

Genitals

Painless

Self-resolving

15

Syphilis

 Varied skin manifestations

 Secondary

 Disseminating phase

 Flu-like symptoms, Lymphadenopathy

 Maculopapular rash - Nonpruritic, Palm/soles involved

 Condyloma lata, Copper penny spots

 Pustules, Mucous patches

 Alopecia

16

Erythema migrans

 Lyme disease

 Bite from Ixodes tick

 Borrelia burgdorferi

 Pathognomonic “target” or “bull's eye” early disease

17

Fungal causes of nodules 

 Cryptococcus

 Histoplasma

 Coccidioides

 Sporotrichosis

18

Nocardia characteristics 

 Direct inoculation of organisms into the skin

 During gardening or farming;

 Puncture by a thorn or splinter

 Manifestations

 Ulcerations, cellulitis, nodules, and subcutaneous abscesses

 May involve regional lymphatics, producing a nodular lymphangitis

 "sporotrichoid nocardiosis”

19

Nocardia  Diagnosis

 Modified AFB stain

 Less mycolic acid in cell wall than

mycobacterial species (AFB+)

 Nocardia easily decolorizes, will not be visible on normal AFB stain

 Culture

 Variable colony morphology

 

20

Sporotrichosis characteristics 

 Sporothrix schenkii

 Inoculated by organic matter  Rose bush

 Gardeners

 Erythematous nodules

 Ulceration

 Follow lymphatics

 “sporotrichoid spread”

21

Cryptococcus characteristics (can cause nodules

 Large capsule

 india ink stain

 CNS, lung, skin

 Immunosuppressed, HIV

 Bird droppings, soil

22

 Molluscum contagiosum can cause nodules (characteristics )

 poxvirus

 spread by contact

 common in childhood

 seen in immunosuppression, HIV

23

Noninfectious nodules

 Erythema nodosum

 Systemic lupus erythematosis

 Sarcoidosis

 Ulcerative colitis

 Crohn’s disease

 Medications

 Neoplasm

24

Vesicles (<0.5cm)

 Elevated; Fluid-filled

 Herpes viruses – dsDNA viruses

 Erythematous base

 Tzank smear, multinucleated giant cells

25

Varicella zoster

 Chickenpox

 Dermatomal reactivation (shingles)

26

 HSV vesicle characteristics 

 dsDNA

Clustered lesion

Type 1 perioral

 Type 2 genital

 

27

 CoxsackieTypeA

 Herpangina –

 painful palatal ulcers (HFM disease)

28

 Coxsackie Type B

 Cardiac manifestations

 Myocarditis, cardiomyopathy, arrhythmias

 Pleurodynia

29

Bullous lesions size

(>0.5 cm)

30

Staphylococcal scalded skin syndrome (SSSS)

 Systemic spread of Staphylococcus aureus exfoliative toxins (ETs)

 Primary infection localized elsewhere

 Cause intraepidermal splitting through the granular layer by cleavage a desmosomal protein that mediates cell-cell adhesion granular layer.

31

 Vibrio vulnificus

 Following water exposure or ingestion of contaminated seafood (shellfish)

 Severe disease with liver disease

32

Vesiculopustular

Some lesions with clear fluid (vesicular) some with purulent material (pustular)

33

FOLLICULITIS seen in

 Pseudomonas:Hottubexposure

 Staphylococcalfolliculitis

34

Erythema characteristics 

 Diffuseredness,blanching,vasodilatation

 Cellulitis

 Gram positive

 Staph,strep

 Risks – any breach in skin integrity.

 Tinea,venousstasis,onychomycosis

 Treatment – antibiotics, treat underlying cause

35

Erysipelas (erythema) characteristics 

 Group A strep

 Well-demarcated,painful

36

 Lymphangitis characteristics 

 Gram positive – Group A strep, staph

 Follows lymphatics

 “streaking”,associated lymphadenopathy

 Risks – lymph node resection

37

Petechiae (<3 mm) & Purpura (> 3mm)

Characteristics 

 Extravasated blood, thrombosed vessels

 will NOT blanch with pressure

 Purplish in color

38

Neisseria meningitides characteristics 

 Gram negative diplococci

 Capsule inhibits phagocytosis

 IgA protease allows colonization of respiratory tract

 Lipopolysaccharide endotoxin (LPS)

 Most common cause of bacterial meningitis in children & young adults; Rapidly fatal if untreated

 Meningococcemia- Petechial rash; Skin, mucous membranes; Conjunctivae

 Risks:Terminal complement deficiency (C5-C8)

39

Rickettsia rickettsii (Rocky Mountain Spotted Fever)

 Small intracellular gram negative coccobacilli

 Tick vector (Dermacentor)

 Rash starts on palms & soles, spreads to trunk and face

 “spotless RMSF”

40

Monomicrobial (“Flesh-eating bacteria”) necrotizing fascitis 

 Group A beta-hemolytic streptococci (GAS)

 Pyrogenic exotoxins act as superantigens and trigger massive cytokine release, causing sepsis and shock

 GAS is susceptible to bacitracin

 Also S. aureus

41

 Polymicrobial necrotizing fascitis 

 Gram positive: streptococci

 Gram negative: Enterobacteriaceae

       E. coli, Enterobacter, Klebsiella, Proteus

 At least ONE anaerobe: Bacteroides or Peptostreptococcus

42

Clostridial myonecrosis cultures 

 Double zone of hemolysis with an inner zone of β hemolysis surrounded by an outer zone of partial hemolysis

 Reverse CAMP test on plate with Group B strep (S. agalactiae)