Varicella Zoster Infection

8/7/2019 Varicella Zoster Infection

1/46

ID conference


2/46

A 46 year old woman

Admission date : 21/2/54

Case SLE Dx 2550

DLE

ANA speckle pattern titer 1:1280

Anti nRNP/Sm +ve, Anti SS-A +ve Current medication HCQ 1x1, Prednisolone 7.5

mg/day


3/46

Hospital course Overlap syndrome (SLE with scleroderma)

Develop RPGN >> Kidney biopsy : LN class II

with severe vascular occlusion Double pulse methylprednisolone and IVCY 2

courses 19/1/54

Prednisolone 15 mg/day

ESRD>> regular HD 31/1/54

This admission due to volume overload


4/46

Hospital course VAP with ARDS 13/3/54

Transfer to MICU 17/3/54

Sputum culture : P. aeruginosa Rx with Ceftazidime for 14 days

Weaning ventilator 27/3/54


5/46

Hospital course Chicken pox

30/3/54 developed papulovesicular rash at Ltarm and Lt thigh

History of exposure to chicken pox at RCU 10-14/3/54

CBC : WBC 15,200 PMN 73% Band 5%Eo 2% L 11% Hct 22% Plt 225,000

LFT : D. bili 0.12 T. bili 0.27SGOT 58 SGPT 24


6/46

Hospital course Isolation

Acyclovir 250 mg IV q 8 hr

No development of new lesions and turn to crustin 3 days

Continue acyclovir for 7 days


7/46

Varicella-zoster

infection


8/46

Varicella-zoster virus (VZV) :

herpesviruses

Distinct forms of disease: Varicella (chickenpox): Primary VZV infection

results in the diffuse vesicular rash.

Herpes zoster(shingles): Endogenous

reactivation of latent VZV typically results in alocalized skin infection


9/46


10/46

Transmission routesAirborne transmission

Contact with aerosolized droplets from

nasopharyngeal secretions

Direct cutaneous contact with vesicle fluid

from skin lesions


11/46

Viremia Double-stranded, linear DNA virus

Lipid-containing envelope with glycoproteinspikes.

Localized replication with concurrent replication inregional lymph nodes by 4-6 days

Primary viremic phase with seeding of thereticuloendothelial system

Secondary phase : after 9 days and persiststhrough the development of skin lesions


12/46

Incubation period Incubation period : 8 -21 days

Average : 14-16 days

Infectivity : last from 48 hours prior to the onset ofrash until skin lesions have fully crusted.

Administration of varicella zoster immune

globulin (VZIG) following exposure can prolong

the incubation period from 21 days to 28 days.


13/46

Reinfection

Second episodes of varicella infection in

immunocompetent individuals rarely occur

Subclinical reinfection with VZV is common


14/46

CLINI

CALMANIFES

TATIONS

Occurs during childhood

Benign self-limited illness

Severe disease : adolescents, adults, andimmunosuppressed or

immunocompromised

Secondary cases : more severe thanprimary cases


15/46

Uncomplicated varicella

Develop within fifteen days after the exposure

Prodrome of fever, malaise, or pharyngitis, loss of

appetite Development of a generalized vesicular rash within

24 hours.


16/46

Macule, papule, pustule, vesicular rash : formation

generally stops within 4 days

Pruritic

Crusted papules : 6 days in normal host

Different stages

Face, trunk and extremities

Crusts tend to fall off within about one to two weeks

Temporary area of hypopigmentation


17/46


18/46

IMMUNOS

UPPRESSED

HOS

TS

Underlying malignancy

Steroid use or immunosuppressive therapy

HIV infection

Solid organ transplantation


19/46

Clinical manifestation

Vesicles > 1 week

Large and hemorrhagic skin lesions

Susceptible for disseminated varicella

Disseminated intravascular coagulation


20/46

Diagnosis Clinical signs and symptoms

Tzanck smear Multinucleated giant cell


21/46

Laboratory testing

PCR : rapid and sensitive

Specimen from skin lesion, CSF, BAL, blood

Direct fluorescent antibody (DFA) active vesicular skin lesions

Serologic testing :

protection against subsequent infection.


22/46

Complication

Skin/soft tissue infections

Bacterial skin infections are one of the most

common complications. Streptococcal or staphylococcal pathogens.

Invasive group A streptococcal infections :

cellulitis, myositis/necrotizing fasciitis,

bacteremia, streptococcal toxic shock syndrome.


23/46

Complication

Neurologic complications

Encephalitis

Reye syndrome Transient focal deficits

Aseptic meningitis

Transverse myelitis


24/46

Complication: Encephalitis

Acute cerebellar ataxia : children Complete recovery

Diffuse encephalitis : adult delirium, seizures, and focal neurologic signs

20% of varicella-related hospitalizations

Develop toward the end of the first week


25/46

Complication

Pneumonia

Risk factors : cigarette smoking, pregnancy,

immunosuppression, and male sex Insidious onset within one to six days :

progressive tachypnea, dyspnea, and dry cough,hemoptysis


26/46

Complication

Hepatitis Asymptomatic or subclinical transaminase

elevation

Immunosuppressed hosts including transplantrecipients and AIDS patients

Acute abdominal or back pain

Fulminant liver failure with disseminatedintravascular coagulation (DIC) andgastrointestinal hemorrhage


27/46

THERAPY

Symptomatictreatment

Antihistamines : symptomatic treatment of

pruritis Acetaminophen : treat fever

Avoid significant excoriation and secondarybacterial infection.


28/46

THERAPY

Antiviral therapy Acyclovir: effective for varicella if given during

the first 24 hours of rash Dose :

Children : 20 mg/kg PO qid for 5 days

Adult : 800 mg IV qid for 5 days

Immunocompromised host: 10 mg/kg IV q 8 hr

(up to 500 mg IV q 8 hr) for 7 days


29/46

Children

Significantly : fewer lesions, reduced the

number of days of fever

Developed equivalent antibody responsesto those given placebo.

No clinically important differences to

complications


30/46

Acyclovir should be given

Older children (greater than 12 years of age)

Secondary household cases

History of chronic cutaneous or cardiopulmonarydisorders, since secondary bacterial infectionsmay have severe consequences

Children taking intermittent oral or inhaled steroidtherapy

Children taking chronic salicylates. (higher risk ofdeveloping Reye syndrome)


31/46

Adult

Most adults have uncomplicated varicella.

Varicella pneumonia has mortality 10-30%.

Acyclovir should be initiated within 24 hr ofsymptom onset.

Acyclovir had no effect on the course of the

illnessafter 25 - 72 hr


32/46

Immunocompromised host Mortality rate of 7-14%

Acyclovir reduced the risk of visceral

dissemination and severe complications Intravenous acyclovir should be given even

if > 24 hours


33/46

Prevention


34/46

Varicella Vaccine Immunogenicity

and Efficacy Detectable antibody

97% of children 12 months-12 years following 1

dose 99% of persons 13 years and older after 2 doses

70%-90% effective against any varicella

disease

95%-100% effective against severe

varicella disease


35/46

Varicella Breakthrough Infection

Immunity appears to be long-lasting for

most recipients

Breakthrough disease much milder than inunvaccinated persons

No consistent evidence that risk of

breakthrough infection increases with timesince vaccination


36/46

Minimum Intervals Between Doses ofV

aricellaV

accine 12 months

through 12 years

of age 13 years of age or

older

3 months

4 weeks


37/46

Varicella

Vaccine

Adverse

Reactions

Local reactions (pain, erythema) 19% (children) 24% (adolescents and adults)

Rash 3%-4% may be maculopapular rather

than vesicular average 5 lesions

Systemic reactions not common


38/46

Post-exposure prophylaxis

ASSESSMENTOF EXPOSURE RISK

Transmission rate 90%

Negative history of varicella No prior vaccination

Close indoor contact lasting one hour or more


39/46


Active immunization

Live attenuated varicella virus vaccines

Contraindicated for immunocompromised hosts prevention of infection and lessening of disease

severity

Ideally administered within 3 days of exposure


40/46


PASSIVE IMMUNIZATION

Effective in prevention 60%

Immunosuppressed patients

Pregnant women

administered within 96 hours of exposure

Monitored for varicella for 28 days

If develop varicella : promp treatment with acyclovir

vaccine should be given after 5 months have passed


41/46


Varicella zoster immune globulin (VZIG)

Dose : 125 units/10 kg (max 625 units)

Intravenous immune globulin (IVIG)

If VariZIG cannot be administered

Dose : 400 mg/kg IV once


42/46

Prevention andcontrol of varicella

in hospitals


43/46

IMPORTANCE OF VARICELLAASA

NOSOC

OMIAL

INFECT

ION Highly contagious

Associated with serious complications

Infection in pregnant women may lead tocongenital varicella syndrome


44/46

Nosocomial exposure to varicella Removal of susceptible staff from patient

contact following VZV exposures

Administration of prophylaxis to patientsand employees

Time and effort of hospital staff inevaluating potential VZV exposures.


45/46

Prevention

Employees without a definitive history of

VZV infection should undergo serologic

testing. Routine varicella immunization for

susceptible health care workers.


46/46

Management of patients exposed toVZV

Confirm source case has VZV infection.

Define exposed patient.

Susceptible patients are placed on airborneprecautions or private negative pressureroom.

Considered for post-exposure prophylaxis.

Documents

Varicella Zoster Infection