ppd values

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ppd values

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15 Posts

vogon77
Forum Senior

Topics: 33
Posts: 73

08/17/04 - 02:13 AM

what r the ppd values at which treatment for TB need to be started

normal person
HIV case/immunocompromised
diabetic

mdwannabe
Forum Guru

Topics: 37
Posts: 1,133

08/17/04 - 06:27 AM

normal -- >9mm induraion (assume acute exposure)
HIV-->5mm induration
Diabetic??? I dunno... I d take 5 mm... but would look carefully at exposure risk.

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Malaysian
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Topics: 28
Posts: 778

08/17/04 - 06:49 AM

Can anyone give a complete comprehensive list of readings for PPD....I think its an important component not only for step 1 but also step 2 so might as well do it in detail.

mash
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Topics: 147
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08/17/04 - 06:55 AM

ppd in HIV +ve pts >5mm induration
in high risk gps >10mm
in low risk pop >15mm

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vogon77
Forum Senior

Topics: 33
Posts: 73

08/17/04 - 02:45 PM

how abt ppd values in patients where they ahve already received BCG vaccine

Ahab
Forum Elite

Topics: 9
Posts: 228

08/17/04 - 03:10 PM

Cant use ppd in those who have had BCG

carmenburana
Forum Junior

Topics: 5
Posts: 41

08/17/04 - 06:44 PM

What if an HIV pt has full-blown AIDS and has little inflam response to ppd? Don't you sometimes treat 'em anyway if they have clinical or epidemiologic factors?

mani
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08/17/04 - 11:02 PM

agree with the values given by mash.
carmenburana, , remeber ppd is not the only test used for Tb diagnosis

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mani
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08/17/04 - 11:02 PM

agree with the values given by mash.
carmenburana, , remembr ppd is not the only test used for Tb diagnosis

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SMALLFIDGET
Forum Junior

Topics: 9
Posts: 72

08/18/04 - 07:59 AM

#10

Excellent Q vogon!! Phew!

Note what I have to say - 1.Cut off values; 2.Induration and not redness!!!

Normal person -
HIV+ case - > 5mm induration - treat
HIV+ case - <5mm (s/o immunocompromisation) - consider INH prophylaxis
Diabetics - 10mm
BCG vaccinated - PPD is not useful

THE FOLLOWING MATERIAL IS WHAT I HAD FOUND SOMETIME BACK:

What constitutes a positive skin test?
1. 5 mm
a) HIV infected persons
b) persons with chest x-rays suggesting previous TB
c) close contacts of persons with active TB
d) patients with organ transplants or other immunosuppressed patients (ie, receiving more than 15 mg/day of prednisone for a month or more)

2. 10 mm
a) immigrants
(1) many of these patients will have recieved BCG vaccination in the past
(2) BCG can cause a false positive skin test but the reaction usually wanes with age
(3) current recommendations are to ignore BCG vaccination when interpreting the PPD skin test
b) health care workers
c) residents and employees in:
(1) prisons and jails
(2) nursing homes
(3) homeless shelters
(4) residential facilities for care of HIV-infected persons
d) low income or medically underserved persons
e) teachers
f) day care workers
g) mycobacteriology laboratory personnel
h) "at risk" medical conditions
(1) diabetes
(2) end stage renal disease
(3) lymphoreticular malignancies
(4) corticosteroid or immunosuppressive drug use
(5) rapid weight loss (more than 10%)
(6) head or neck cancer
(7) gastrectomy or jejunoileal bypass
(6) IV drug use
(7) silicosis

3. 15 mm
a) anyone with no obvious risks of acquiring TB

Who should receive prophylaxis?

1. positive skin test and "at risk" medical conditions:
a) diabetes
b) end stage renal disease
c) lymphoreticular malignancies
d) corticosteroid or immunosuppressive drug use
e) rapid weight loss
f) IV drug use
g) silicosis

2. positive skin test and under age 4

3. close contacts of persons with active TB
a) treat with prophylactic antibiotics if the PPD is positive
b) a positive skin test will not develop for 6-8 weeks therefore it is sometimes advisable to initiate prophylaxis even if the skin test is negative and then discontinue prophylaxis if a second PPD is negative in 12 weeks

4. positive skin test and HIV infection
a) in HIV-infected persons who are anergic and have a documented exposure to someone with active TB, prophylaxis is appropriate
b) in HIV-infected persons who are anergic and live in areas where the prevalence of TB is high, prophylaxis may be appropriate even when the skin test is negative

5. persons who convert the skin test to positive within a 2 year period
a) > 10 mm increase if under 35 years of age
b) > 15 mm increase if over 35 years of age

6. persons under age 35 with a positive PPD skin test and who are:
a) immigrants
b) medically underserved
c) residents of institutions
d) health care workers or staff of chronic care institutions (because of the risk of precipitating an outbreak)
e) positive skin test in a healthy person under 35 years of age with none of the above risk factors is controversial and may be considered on an individual basis

LONG? I am sorry...but hope that helped!

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Alina T
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08/18/04 - 09:41 AM

#11

long but very helpfull. thanks for sharing! smiling face

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carmenburana
Forum Junior

Topics: 5
Posts: 41

08/19/04 - 09:31 AM

#12

"mani" wrote:
agree with the values given by mash.
carmenburana, , remembr ppd is not the only test used for Tb diagnosis

As far as I know, the only real way to make a TB diagnosis is by isolating Acid-fast bacilli, but in most HIV patients, that would happen. The second best way is a clinical picture with a + ppd, but HIV patients often have atypical presentation of TB and the anergy is always an issue. The least desireable way to diagnose is by treating the patient and having them get better. Are there any other ways that you know of? Maybe there is a new, high-tech test?

Ahab
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Topics: 9
Posts: 228

08/19/04 - 09:38 AM

#13

"carmenburana" wrote:

As far as I know, the only real way to make a TB diagnosis is by isolating Acid-fast bacilli, but in most HIV patients, that would happen. The second best way is a clinical picture with a + ppd, but HIV patients often have atypical presentation of TB and the anergy is always an issue. The least desireable way to diagnose is by treating the patient and having them get better. Are there any other ways that you know of? Maybe there is a new, high-tech test?

If you are lucky enough you can get a culture, only problem is it takes 6-8 weeks if I remember correctly

carmenburana
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08/19/04 - 12:44 PM

#14

Thanks ahab!

mani
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08/19/04 - 10:48 PM

#15

for culture there are 2 techniques, one is conventional LJ medium and 2nd is BACTEC medium which can show presence of bug in about 2 wks

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