There is evidence that it may be efficacious in relieving chronic functional symptoms of bloating and flatulence that are common in irritable bowel syndrome (IBS). Rifaximin is licensed by the U.S. Food and Drug Administration to treat traveler’s diarrhea caused by E. coli. Clinical trials have shown that rifaximin is highly effective at preventing and treating traveler’s diarrhea among travelers to Mexico, with few side effects and low risk of developing antibiotic resistance. It is not effective against Campylobacter jejuni, and there is no evidence of efficacy against Shigella or Salmonella species.

It may be efficacious in relieving chronic functional symptoms of bloating and flatulence that are common in irritable bowel syndrome (IBS). There was recently a pilot-study done on the efficacy of rifaximin as a means of treatment for rosacea, according to the study, induced by the co-presence of small intestinal bacterial overgrowth.

In the United States, rifaximin has orphan drug status for the treatment of hepatic encephalopathy.

There was recently a pilot-study done on the efficacy of rifaximin as a means of treatment for rosacea, according to the study, induced by the co-presence of small intestinal bacterial overgrowth.

Martinez-Sandoval F, Ericsson CD, Jiang ZD, Okhuysen PC, Romero JH, Hernandez N, Forbes WP, Shaw A, Bortey E, DuPont HL. (2010 Mar-Apr). “Prevention of travelers’ diarrhea with rifaximin in US travelers to Mexico.”. J Travel Med. 17 (2): 111-7.

Lawrence KR, Klee JA (2008). “Rifaximin for the treatment of hepatic encephalopathy”. Pharmacotherapy 28 (8): 101932.

Peralta S, Cottone C, Doveri T, Almasio PL, Craxi A. Small intestine bacterial overgrowth and irritable bowel syndrome-related symptoms: experience with Rifaximin. World J Gastroenterol. Jun 7 2009;15(21):2628-31.

Pimentel M. Review of rifaximin as treatment for SIBO and IBS. Expert Opin Investig Drugs. Mar 2009;18(3):349-58.

Scarpellini E, Gabrielli M, Lauritano CE, Lupascu A, Merra G, Cammarota G. High dosage rifaximin for the treatment of small intestinal bacterial overgrowth. Aliment Pharmacol Ther. Apr 1 2007;25(7):781-6.

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The important question is how it compares to the simple and widely available skin tuberculin test. Initial studies indicated a sensitivity of 97.2%. However, more recent data from a study in children with active TB disease in the UK suggest that the sensitivity of the T-SPOT.TB may in fact be worse than that of the tuberculin skin test (sensitivity reported as 66% and 82%, respectively)..A metaanalysis of studies in children with active tuberculosis published in 2011 suggests that the sensitivity of the T-SPOT.TB is very similar(but not superior) to that of the tuberculin skin test (pooled sensitivity reported as 84% and 80%, respectively).

Although superiority to skin tubeculin test is not yet established, FDA approved IGRAS test and T0SPot blood tests and the CDC guideline recommends their use. “….. TSTs and IGRAs (QFT-G, QFT-GIT, and T-Spot) may be used as aids in diagnosing M. tuberculosis infection,” the guidelines authors write. “They may be used for surveillance purposes and to identify persons likely to benefit from treatment. Multiple additional recommendations are provided that address quality control, test selection, and medical management after testing.”

As such, this is an FDA approved test but the reliable evidence shows that the expert consensus is that the farther clinical studies are still required. Prospective Comparison of the Tuberculin Skin Test and Interferon-Gamma Release Assays in Diagnosing Infection With Mycobacterium Tuberculosis and in Predicting Progression to Tuberculosis, NCT01622140.

Bamford, A. R J; Crook, A. M; Clark, J. E; Nademi, Z.; Dixon, G.; Paton, J. Y; Riddell, A.; Drobniewski, F. et al. (2009). Comparison of interferon-  release assays and tuberculin skin test in predicting active tuberculosis (TB) in children in the UK: A paediatric TB network study”. Archives of Disease in Childhood 95 (3): 1806.

Ritz, Nicole; Connell, Tom G.; Paxton, Georgia A.; Buttery, Jim P.; Curtis, Nigel; Ranganathan, Sarath C. (2008). “A Three-Way Comparison of Tuberculin Skin Testing, QuantiFERON-TB Gold and T-SPOT.TB in Children”. In Dheda, Keertan. PLoS ONE 3 (7): e2624.

Connell, Thomas G.; Tebruegge, Marc; Ritz, Nicole; Bryant, Penelope A.; Leslie, David; Curtis, Nigel (2010). “Indeterminate Interferon- Release Assay Results in Children”. The Pediatric Infectious Disease Journal 29 (3): 2856.

Jump up ^ Connell, T. G.; Tebruegge, M.; Ritz, N.; Bryant, P.; Curtis, N. (2010). “The potential danger of a solely interferon- release assay-based approach to testing for latent Mycobacterium tuberculosis infection in children”. Thorax 66 (3): 2634

Mandalakas, A. M.; Detjen, A. K.; Hesseling, A. C.; Benedetti, A.; Menzies, D. (2011). “Interferon-gamma release assays and childhood tuberculosis: Systematic review and meta-analysis”. The International Journal of Tuberculosis and Lung Disease 15 (8): 101832.

It is a nephrotoxoc drug and cannot be administered to people with kidney dysfunction, which, however, is common after stem cell transplantation or aggressive chemotherapy. Therefore, some attempt to reconstitute the IV formulation and use it topically. It is a water-soluble polar molecule and is predicted to be absorbable across the gastrointestinal tract following oral administration although. No oral formulations are currently available and bioavailability studies have been performed to a limited extent only in animals. It has been compounded in bases for topical use although topical formulations are prohibitively expensive (approximately $65 US per gram of extemporaneously compounded 3% cidofovir cream or it can be compounded as a 1% solution. There are case reprots of using these preparations for condyloma acumina, veruca vulgaris, laryngeal papillomatosis, Kaposi’s sarcoma, poxvirus infections and herpetic infections.

De Clercq and Holy demonstrated that topical cidofovir was effective against human herpesvirus types 1 and 2 and thymidine kinase deficient herpesvirus type 1 in mice. They demonstrated that its efficacy was superior to acyclovir. Snoeck et al reported successful the use of topical cidofovir in 2 patients, one with AIDS and the othe, a bone amrrow transplant patient,  with resistant herpesvirus infections. Lateef et al used a topical preparation for a 4-year-old child with AIDS and a large facial ulcer secondary to herpesvirus type 1. Other case reprots were published by C.R.SIms in 2007, B. Muluneh in 2012

Lalezari et al reported a randomized, double blind, placebo controlled phase I/II clinical study of cidofovir gel in 30 patients with AIDS, all of whom had acyclovir-resistant herpes simplex infections. Eleven patients received 0.3% gel, nine patients received 1.0% gel and 10 were treated with placebo once a day for 5 days. Fifty percent of cidofovir patients had at least 50% improvement in infection in contrast with no improvement in the placebo patients. Thirty percent of the cidofovir treated patients had complete healing, compared with none of the placebo treated patients. The median time for negative viral cultures to be obtained from lesions in the cidofovir treated group was 2 days. Eighty seven per cent of CDV treated patients and no placebo treated patients developed negative viral cultures. Application site reactions occurred in 25 % of cidofovir-treated patients and in 20% of placebo-treated patients. Of the 6 patients treated with CDV who had complete healing, the response was sustained in 3.

Sacks et al described the successful use of cidofovir topical gel in otherwise healthy patients with recurrent genital herpes infection. Ninety-six patients were randomized in a double blind, placebo controlled trial. All patients were confirmed by viral culture or serology as having recurrent genital herpes simplex. Treatment consisted of a single application of cidofovir gel 1%, 3%, 5% or placebo within 12 hours of an outbreak. All patients treated with cidofovir showed a decrease both in median time for cultures to become negative and in the number of days to complete healing. Sacks et al concluded that topical cidofovir gel was well tolerated and possessed significant antiviral activity.

In conclusion, there a a number of case reports and series that support this drug, as well as two Phase II studies, one randomized. 1%, 3% and 5% solutions have shown activity.
Edward J. Zabawski,  Review of Topical and Intralesional Cidofovir
Jr.Dermatology Online Journal 6(1): 3, 2000

De Clercq E. Therapeutic potential of Cidofovir (HPMPC, Vistide) for the treatment of DNA virus (i.e. herpes-, papova-, pox- and adenovirus) infections. Verh K Acad Geneeskd Belg 1996;58(1):19-47; discussion 47-9.

Snoeck R, Andrei G, Gerard M, Silverman A, Hedderman A, Balzarini J, Sadzot-Delvaux C, Tricot G, Clumeck N, De Clercq E. Successful treatment of progressive mucocutaneous infection due to acyclovir- and foscarnet-resistant herpes simplex virus with (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine (HPMPC). Clin Infect Dis 1994;18(4):570-8.

Lateef F, Don PC, Kaufmann M, White SM, Weinberg JM. Treatment of acyclovir-resistant, foscarnet-unresponsive HSV infection with topical cidofovir in a child with AIDS [letter; comment] Arch Dermatol 1998;134(9):1169-70.

Lalezari J, Schacker T, Feinberg J, Gathe J, Lee S, Cheung T, Kramer F, Kessler H, Corey L, Drew WL, Boggs J, McGuire B, Jaffe HS, Safrin S. A randomized, double-blind, placebo-controlled trial of cidofovir gel for the treatment of acyclovir-unresponsive mucocutaneous herpes simplex virus infection in patients with AIDS. J Infect Dis 1997;176(4):892-8.

Sacks SL, Shafran SD, Diaz-Mitoma F, Trottier S, Sibbald RG, Hughes A, Safrin S, Rudy J, McGuire B, Jaffe HS. A multicenter phase I/II dose escalation study of single-dose cidofovir gel for treatment of recurrent genital herpes. Antimicrob Agents Chemother 1998;42(11):2996-9.

Sims CR, Thompson K, Chemaly RF, Shpall EJ, Champlin RE, Safdar A. Oral topical cidofovir: novel route of drug delivery in a severely immunosuppressed patient with refractory multidrug-resistant herpes simplex virus infection.Transpl Infect Dis. 2007 Sep;9(3):256-9.

B. Muluneh et al, Successful clerance of acyclovir resistant, foscarnet refractory herpes virus lesions with topical cidifivit in allogneic hematoppoietic stem cell transplant patient, J Oncol Pharm Pract, published online 24 May 2012

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While retrospective studies indicate that long-term steroid use increases the risk of PCP infection it is not known how these patients should be prophylaxed. The threshold for potential infection that warrants prophylaxis with its costs in side effects and expense is unknown, and the critical amount of immunosuppression necessary to increase risk for PCP is also unknown. Prophylaxis has been suggested for patients immunosuppressed owing to an underlying disease or immunosuppressive therapy. In some cancer centers, patients who receive corticosteroid therapy for longer than 4 weeks at a dose equivalent to 20 mg of prednisone per day are routinely are given PCP prophylaxis, as well as those in high-risk groups such as bone marrow transplant recipients and children with ALL.

In 2009, Kovacs and Masur summarized the first 100 years since identification of Pneumocystis. They concluded that in HIV-negative patients there is no reliable laboratory marker for risk of this infection, but that in these patients PCP is more likely to be an acute illness causing severe respiratory distress of rapid onset when compared with HIV-positive patients. That makes routine prophylaxis more reasonable. Their recommended approach is to use PCP prophylaxis in patients receiving at least 20 mg of prednisone per day for at least 1 month. They also note that steroid therapy can accelerate symptomatic and physiologic improvement and improve survival in patients with moderate or severe PCP. Since steroids are in themselves immunosupressive, management of corticosteroids in PCP-infected patients is quite complex.

Kovacs JA, Masur H. Evolving health effects of Pneumocystis: one hundred years of progress in diagnosis and treatment. JAMA. 2009;301:2578-2585.

Green H, Paul M, Vidal L, Leibovici L.Prophylaxis of Pneumocystis pneumonia in immunocompromised non-HIV-infected patients: systematic review and meta-analysis of randomized controlled trials. Mayo Clin Proc. 2007 Sep;82(9):1052-

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In two recent studies, the addition of RSV immune globulin (palivizumab at 15 mg/kg IM monthly) to traditional ribavirin therapy has shown promise in preventing the progression of RSV upper respiratory infection(URI) to lower respiratory disease and also in the treatment of RSV pneumonia. The key is being vigilant about URI and making the diagnosis quickly. It is imperative to determine the etiology of a URI in an stem cell recipient, if possible, because respiratory syncytial virus (RSV), influenza, parainfluenza, and adenovirus URIs can progress to more serious Lower Respiratory Infection. Appropriate routine diagnostic samples to investigate URO in recent transplant recipients include nasopharyngeal washes, swabs or aspirates; throat swabs (in combination with nasal samples); and bronchoalveolar lavage (BAL) fluid. Without an URI, prophylactic use of Ribavirin alone is currently experimental.

Jharna N. Shah and Roy F. Chemaly, Management of RSV infections in adult recipients of hematopoietic stem cell transplantation
Blood March 10, 2011 vol. 117 no. 10 2755-2763

D. McCoy, E. Wong, A.G. Kuyumjian, M.A. Wynd, R. Sebti, G.B. Munk. Treatment of respiratory syncytial virus infection in adult patients with hematologic malignancies based on an institution-specific guideline. Transpl Infect Dis 2011: 13: 117–121.

Marcie Tomblyn, Tom Chiller, Hermann Einsele, Ronald Gress, Kent Sepkowitz, Jan Storek,
John R. Wingard, Jo-Anne H. Young, Michael A. Boeck Guidelines for Preventing Infectious Complications among Hematopoietic Cell Transplantation Recipients: A Global Perspective Biol Blood Marrow Transplant 15: 1143-1238 (2009)

Read the Layperson version here.

In two recent studies, the addition of RSV immune globulin (palivizumab at 15 mg/kg IM monthly) to traditional ribavirin therapy has shown promise in preventing the progression of RSV upper respiratory infection(URI) to lower respiratory disease and also in the treatment of RSV pneumonia. The key is being vigilant about URI and making the diagnosis quickly. It is imperative to determine the etiology of a URI in an stem cell recipient, if possible, because respiratory syncytial virus (RSV), influenza, parainfluenza, and adenovirus URIs can progress to more serious Lower Respiratory Infection. Appropriate routine diagnostic samples to investigate URO in recent transplant recipients include nasopharyngeal washes, swabs or aspirates; throat swabs (in combination with nasal samples); and bronchoalveolar lavage (BAL) fluid. Without an URI, prophylactic use of Ribavirin alone is currently experimental. Combinations with immunomodulators appear more effective than ribavirin alone for active infection.

A recent review (Jharna et al) enunciated some concerns about the few available studies of oral ribaviarin for HSCT recipients. Oral ribavirin has been shown be well tolerated in HSCT patients with RSV infection. It is well absorbed, with 50% bioavailability through first-pass metabolism. It is less costly than the intravenous and the aerosolized forms and does not require hospitalization of the patient. However, the use of oral ribavirin has often been associated with the development of anemia, which is usually reversible with no delay in engraftment, and with nausea. Moreover, absorption of oral ribavirin in patients with GVHD may not be optimal and was not studied. This may account for worse outcomes in the studies involving oral ribavirin. Prophylactic ribavivrin is not supported by guidelines after the immediate post transplant period and certainly no longer than a year.

Jharna N. Shah and Roy F. Chemaly, Management of RSV infections in adult recipients of hematopoietic stem cell transplantation
Blood March 10, 2011 vol. 117 no. 10 2755-2763

D. McCoy, E. Wong, A.G. Kuyumjian, M.A. Wynd, R. Sebti, G.B. Munk. Treatment of respiratory syncytial virus infection in adult patients with hematologic malignancies based on an institution-specific guideline. Transpl Infect Dis 2011: 13: 117–121.

Marcie Tomblyn, Tom Chiller, Hermann Einsele, Ronald Gress, Kent Sepkowitz, Jan Storek,
John R. Wingard, Jo-Anne H. Young, Michael A. Boeck Guidelines for Preventing Infectious Complications among Hematopoietic Cell Transplantation Recipients: A Global Perspective Biol Blood Marrow Transplant 15: 1143-1238 (2009)

Jharna N. Shah and Roy F. Chemaly Management of RSV infections in adult recipients of hematopoietic stem cell transplantation Blood 10, 2011 vol. 117 no. 10 2755-2763

D. McCoy, E. Wong, A.G. Kuyumjian, M.A. Wynd, R. Sebti, G.B. Munk. Treatment of respiratory syncytial virus infection in adult patients with hematologic malignancies based on an institution-specific guideline. Transpl Infect Dis 2011: 13: 117–121.

Marcie Tomblyn, Tom Chiller, Hermann Einsele, Ronald Gress, Kent Sepkowitz, Jan Storek, John R. Wingard, Jo-Anne H. Young, Michael A. Boeck Guidelines for Preventing Infectious Complications among Hematopoietic Cell Transplantation Recipients: A Global Perspective Biol Blood Marrow Transplant 15: 1143-1238 (2009)

Jharna N. Shah and Roy F. Chemaly, Management of RSV infections in adult recipients of hematopoietic stem cell transplantation
Blood March 10, 2011 vol. 117 no. 10 2755-2763

D. McCoy, E. Wong, A.G. Kuyumjian, M.A. Wynd, R. Sebti, G.B. Munk. Treatment of respiratory syncytial virus infection in adult patients with hematologic malignancies based on an institution-specific guideline. Transpl Infect Dis 2011: 13: 117–121.

Boeckh M, et al. Randomized controlled multicenter trial of aerosolized ribavirin for respiratory syncytial virus upper respiratory tract infection in hematopoietic cell transplant recipients. Clin Infect Dis 2007;44:245-9.

Ghosh S, et al. Respiratory syncytial virus upper respiratory tract illnesses in adult blood and marrow transplant recipients: combination therapy with aerosolized ribavirin and intravenous immunoglobulin. Bone Marrow Transplant 2000;25:751-5.

Marcie Tomblyn, Tom Chiller, Hermann Einsele, Ronald Gress, Kent Sepkowitz, Jan Storek,
John R. Wingard, Jo-Anne H. Young, Michael A. Boeck Guidelines for Preventing Infectious Complications among Hematopoietic Cell Transplantation Recipients: A Global Perspective Biol Blood Marrow Transplant 15: 1143-1238 (2009)

Read the Layperson version here.