Originally Posted by jzon
influence of antibiotics on psa level;specifically levaquin
Welcome to the Board! You do have a gift for keeping it brief!
I won't be as brief because it's important you know some key information that sets the stage, and because other board participants may be interested in the important question you raise. That other information includes: infection and PSA, how PSA behaves when there is infection, and other influences on PSA. If you know all that, skip to "Using PubMed to answer your question." Infection and PSA.
The first point, which you probably already know, is that infection or inflammation of the prostate can cause PSA to increase, sometimes by a lot. I've head an expert say that it can raise it up to 50, and I heard of one case where it rose to around 200
before dropping back to normal when a treatment was finally found for the infection that caused the rise
. Antibiotics are often used to treat the root cause of the problem - the infection.
The problem is that it's not so easy to figure out the bacterial cause - which one is it?
Sometimes urine or tissue cultures can be used successfully to identify the culprit, but often the cause is still unknown. Part of the reason that some men get no benefit from an antibiotic, even when it happens to be on target, is that the particular bacterium causing the problem may have developed resistance to the particular drug.
The key issue here is that smart use of antibiotics can eliminate many PSA rises that would otherwise trigger a doctor's desire to do a prostate biopsy
; this is a point made in some of the papers on the issue that are listed below. The way PSA behaves due to various influences.
A second point is that a PSA level that is affected by infection tends to jump around. In contrast, PSA that is increasing only because of infection rises at a steady
"exponential" rate as one cancer cell splits into two, two into four ... four hundred into eight hundred, etc. If you graph the points, it will be an upward curving line for cancer, or a straight line for cancer if you plot it on "log paper". Benign prostatic hyperplasia (non-cancerous prostate enlargement) will also increase PSA in a harmless way (meaning non-cancerous), as each cubic centimeter of added healthy prostate growth accounts for about 0.066 units of PSA (nano grams per milliliter, or ng/ml). It's quite possible to have a PSA that is influenced by a combination of infection, BPH, and cancer, or by any two. There are also some less common influences on PSA, and certain physical events, such as very recent ejaculation, a prostate biopsy, and perhaps riding horseback or on a motorcycle may also influence PSA. Using PubMed to answer your question.
But you asked about the influence of two specific drugs. I haven't used either and know nothing about them off the top of my head, so I did what I usually do to learn about an answer - the same thing you can and should do for free (our taxpayer dollars at work) - and searched www.pubmed.gov for " PSA AND (levaquin OR clindamycin) ". (You don't need the quotes in the search block. We can use PubMed, a site belonging to US Government's National Institutes of Health unit known as the National Library of Medicine, on this board because it is sponsored by the Government. You can copy that search, or just type in your own fresh search, including the parentheses to get the same PubMed results with either one drug, the other, or both, .
I got ten hits. The list is short enough that I'll include them all here so you can see what PubMed can do for you. Sometimes the board monitors determine that too much is being brought in even if from approved web sites, but I hope this list of papers will be acceptable.
Items 1 - 10 of 10 One page.
1: Serum PSA and percent free PSA value changes after antibiotic treatment. A diagnostic method in prostate cancer suspects with asymptomatic prostatitis.
Kobayashi M, Nukui A, Morita T.
Urol Int. 2008;80(2):186-92. Epub 2008 Mar 19.
PMID: 18362491 [PubMed - indexed for MEDLINE]
2: Ofloxacin-delivery system of a polyanhydride and polylactide blend used in the treatment of bone infection.
Chen L, Wang H, Wang J, Chen M, Shang L.
J Biomed Mater Res B Appl Biomater. 2007 Nov;83(2):589-95.
PMID: 17410574 [PubMed - indexed for MEDLINE] My comment: notice that this hit results from PSA for a different meaning: "poly(sebacic anhydride) (PSA)"; while it does relate to infection, it is probably not relevant. This kind of irrelevant result can happen with PubMed searches unless you really spell out your search terms, such as "prostate specific antigen" instead of just PSA. I'm usually not so precise and just deal with the minor amount of clutter.
3: Effects of antibacterial therapy on PSA change in the presence and absence of prostatic inflammation in patients with PSA levels between 4 and 10 ng/ml.
Kaygisiz O, Uğurlu O, Koşan M, Inal G, Oztürk B, Cetinkaya M.
Prostate Cancer Prostatic Dis. 2006;9(3):235-8. Epub 2006 May 23.
PMID: 16718277 [PubMed - indexed for MEDLINE]
4: Treatment of chronic bacterial prostatitis with levofloxacin and ciprofloxacin lowers serum prostate specific antigen.
Schaeffer AJ, Wu SC, Tennenberg AM, Kahn JB.
J Urol. 2005 Jul;174(1):161-4.
PMID: 15947609 [PubMed - indexed for MEDLINE]
5: PSA decrease after levofloxacin therapy in patients with histological prostatitis.
Guercio S, Terrone C, Tarabuzzi R, Poggio M, Cracco C, Bollito E, Scarpa RM.
Arch Ital Urol Androl. 2004 Dec;76(4):154-8.
PMID: 15693428 [PubMed - indexed for MEDLINE]
6: Effect of antibiotic treatment on serum PSA and percent free PSA levels in patients with biochemical criteria for prostate biopsy and previous lower urinary tract infections.
Lorente JA, Arango O, Bielsa O, Cortadellas R, Gelabert-Mas A.
Int J Biol Markers. 2002 Apr-Jun;17(2):84-9.
PMID: 12113586 [PubMed - indexed for MEDLINE]
7: [Effect of antibiotic treatment on PSA and percentage of free PSA in patients with biochemical criteria of prostatic biopsy]
Lorente Garín JA, Arango Toro O, Bielsa Gali O, Cortadellas Angel R, Gelabert-Mas A.
Actas Urol Esp. 2001 Oct;25(9):637-44. Spanish.
PMID: 11765547 [PubMed - indexed for MEDLINE]
Related Articles Free article at journal site
8: Prostate-specific antigen (PSA) value change after antibacterial therapy of prostate inflammation, as a diagnostic method for prostate cancer screening in cases of PSA value within 4-10 ng/ml and nonsuspicious results of digital rectal examination.
Karazanashvili G, Managadze L.
Eur Urol. 2001 May;39(5):538-43.
PMID: 11464034 [PubMed - indexed for MEDLINE]
9: Characterization of synergy between ofloxacin, ceftazidime, and tobramycin against Pseudomonas aeruginosa.
Madaras-Kelly KJ, Moody J, Larsson A, Baeker Hovde L, Rotschafer JC.
Chemotherapy. 1997 Mar-Apr;43(2):108-17.
PMID: 9084919 [PubMed - indexed for MEDLINE]
10: A pharmacodynamic evaluation of ciprofloxacin and ofloxacin against two strains of Pseudomonas aeruginosa.
Madaras-Kelly KJ, Larsson AJ, Rotschafer JC.
J Antimicrob Chemother. 1996 Apr;37(4):703-10.
PMID: 8722536 [PubMed - indexed for MEDLINE]
Related Articles Free article at journal site Tips for using PubMed for your question.
Each hit includes a link to relate articles, and as you can see, a couple of them have links to free copies of the entire paper.
If the study has an abstract - a short, usually half-page description of the study, you can get that by clicking on the blue hypertext authors list at PubMed. Most papers will offer an abstract, and it's available to us for free. When you read the abstracts, there will be a lot of highly technical language that is hard for us layman to understand. However, usually at least the introduction and conclusions will be fairly easy to understand. I've gotten used to medical research and have a research background, so I can probably help if you have questions.
I've read most of these abstracts, and some do not mention the drugs used in the studies, just referring to "antibiotics." I'm fairly sure the PubMed search would not have picked up the result unless at least one of the drugs you were interested in was mentioned in the full body of the study. You usually have to translate the brand name of the drug into its generic name.
If you have follow-up questions, including questions, please feel free to ask. One of us will probably have the answer. Also, if you dig into this, please share what you learn. You might also want to broaden your search to include just antibiotics instead of limiting it to the two in your question.
I hope you will post again.