Infections in Patients with Multiple Myeloma in the Era of Novel Agents and Stem Cell Therapies

Multiple myeloma is a common hematologic malignancy that is associated with reduced cellular as well as humoral immunity ultimately causing various infectious complications. The recent advances in the management of myeloma have led not only to prolonged survival but also to shifts in the incidence as well as the spectrum of infections encountered. This book chapter will be an updated review on the infectious complications in patients with multiple myeloma in the era of novel agents, stem cell therapies, and monoclonal antibodies. It will cover causes of immunosuppression, timing, and types as well as management of the various infections reported with various therapeutic modalities that are currently utilized in the management of myeloma patients

The Rising Role of Mesenchymal Stem Cells in the Treatment of Various Infectious Complications

Mesenchymal stem cells are heterogenous adult multipotent stromal cells that can be isolated from various sources including: bone marrow, peripheral blood, umbilical cord blood, dental pulp, and adipose tissue. They have certain immunomodulatory, immunosuppressive, and antimicrobial properties that enable them to have several therapeutic and clinical applications including: treatment of autoimmune disorders, role in hematopoietic stem cell transplantation and regenerative medicine, as well as treatment of various infections and their associated complications such as septic shock and acute respiratory distress syndrome. Although more success has been achieved in preclinical trials on the use of mesenchymal stem cells in animal models than in human clinical trials, particularly in septic shock and Chagas disease, more progress has been made in both disorders after the recent use of specific sources and certain doses of mesenchymal stem cells. Nevertheless, the utilization of this type of stem cells has shown remarkable progress in the treatment of few infections such as tuberculosis. The clinical application of mesenchymal stem cells in the treatment of several diseases still faces real challenges that need to be resolved. The following book chapter will be an updated review on the role of mesenchymal stem cells in various infections and their complications

Brucella bacteremia in patients with acute leukemia: a case series

<p>Abstract</p> <p>Background</p> <p>Brucellosis may cause serious infections in healthy individuals living in countries that are endemic for the infection. However, reports of brucella infections in immunocompromised hosts are relatively rare.</p> <p>Case Presentations</p> <p>Reported here are two patients with acute leukemia who developed <it>Brucella melitensis </it>bacteremia during their follow up at the Armed Forces Hospital in Riyadh. The first patient developed <it>B. melitensis </it>bacteremia during the transformation of his myelodysplasia into acute myeloid leukemia. The second patient developed <it>B. melitensis </it>bacteremia while his acute lymphoblastic leukemia was under control. Interestingly, he presented with acute cholecystitis during the brucella sepsis. Both brucella infections were associated with a marked reduction in the hematological parameters in addition to other complications. The bacteremic episodes were successfully treated with netilmicin, doxycycline and ciprofloxacin.</p> <p>Conclusion</p> <p>Brucellosis can cause systemic infections, complicated bacteremia and serious morbidity in patients with acute leukemia living in endemic areas. These infections may occur at the presentation of the leukemia or even when the leukemia is in remission. Nevertheless, the early diagnosis of brucellosis and the administration of appropriate antimicrobial therapy for sufficient duration usually improves the outcome in these immunocompromised patients.</p

The antibacterial properties of Malaysian tualang honey against wound and enteric microorganisms in comparison to manuka honey

<p>Abstract</p> <p>Background</p> <p>Antibiotic resistance of bacteria is on the rise, thus the discovery of alternative therapeutic agents is urgently needed. Honey possesses therapeutic potential, including wound healing properties and antimicrobial activity. Although the antimicrobial activity of honey has been effectively established against an extensive spectrum of microorganisms, it differs depending on the type of honey. To date, no extensive studies of the antibacterial properties of tualang (<it>Koompassia excelsa</it>) honey on wound and enteric microorganisms have been conducted. The objectives of this study were to conduct such studies and to compare the antibacterial activity of tualang honey with that of manuka honey.</p> <p>Methods</p> <p>Using a broth dilution method, the antibacterial activity of tualang honey against 13 wound and enteric microorganisms was determined; manuka honey was used as the control. Different concentrations of honey [6.25-25% (w/v)] were tested against each type of microorganism. Briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) against each type of microorganism, followed by more assays within a narrower dilution range to obtain more precise MIC values. MICs were determined by both visual inspection and spectrophotometric assay at 620 nm. Minimum bactericidal concentration (MBC) also was determined by culturing on blood agar plates.</p> <p>Results</p> <p>By visual inspection, the MICs of tualang honey ranged from 8.75% to 25% compared to manuka honey (8.75-20%). Spectrophotometric readings of at least 95% inhibition yielded MIC values ranging between 10% and 25% for both types of honey. The lowest MBC for tualang honey was 20%, whereas that for manuka honey was 11.25% for the microorganisms tested. The lowest MIC value (8.75%) for both types of honey was against <it>Stenotrophomonas maltophilia</it>. Tualang honey had a lower MIC (11.25%) against <it>Acinetobacter baumannii </it>compared to manuka honey (12.5%).</p> <p>Conclusion</p> <p>Tualang honey exhibited variable activities against different microorganisms, but they were within the same range as those for manuka honey. This result suggests that tualang honey could potentially be used as an alternative therapeutic agent against certain microorganisms, particularly <it>A. baumannii </it>and <it>S. maltophilia</it>.</p

Successful Management of Multifactorial Colitis in a Recipient of Hematopoietic Stem Cell Transplant: A Case Report

Recipients of allogeneic hematopoietic stem cell transplant can develop life-threatening complications at any time following their transplants. These complications require repeated clinical assessment, appropriate and thorough screening as well as a comprehensive management approach. We report a young adult male who received a sibling allograft in the second complete remission of his acute lymphoblastic leukemia at King Faisal Specialist Hospital and Research Centre in Riyadh. The patient developed severe colitis which was caused by: acute exacerbation of chronic graft versus host disease of the lower gastrointestinal tract, cytomegalovirus disease of the colon and a superadded Salmonella infection caused by food poisoning. The multifactorial colitis was properly investigated and successfully managed. To our knowledge, this is the first case of multifactorial colitis in a recipient of hematopoietic stem cell transplant