Targeting ectromelia virus and TNF/NF-κB or STAT3 signaling for effective treatment of viral pneumonia.

Viral causes of pneumonia pose constant threats to global public health, but there are no specific treatments currently available for the condition. Antivirals are ineffective when administered late after the onset of symptoms. Pneumonia is caused by an exaggerated inflammatory cytokine response to infection, but tissue necrosis and damage caused by virus also contribute to lung pathology. We hypothesized that viral pneumonia can be treated effectively if both virus and inflammation are simultaneously targeted. Combined treatment with the antiviral drug cidofovir and etanercept, which targets tumor necrosis factor (TNF), down-regulated nuclear factor kappa B-signaling and effectively reduced morbidity and mortality during respiratory ectromelia virus (ECTV) infection in mice even when treatment was initiated after onset of clinical signs. Treatment with cidofovir alone reduced viral load, but animals died from severe lung pathology. Treatment with etanercept had no effect on viral load but diminished levels of inflammatory cytokines and chemokines including TNF, IL-6, IL-1ß, IL-12p40, TGF-ß, and CCL5 and dampened activation of the STAT3 cytokine-signaling pathway, which transduces signals from multiple cytokines implicated in lung pathology. Consequently, combined treatment with a STAT3 inhibitor and cidofovir was effective in improving clinical disease and lung pathology in ECTV-infected mice. Thus, the simultaneous targeting of virus and a specific inflammatory cytokine or cytokine-signaling pathway is effective in the treatment of pneumonia. This approach might be applicable to pneumonia caused by emerging and re-emerging viruses, like seasonal and pandemic influenza A virus strains and severe acute respiratory syndrome coronavirus 2.

NPP-669, a prodrug of cidofovir, is highly efficacious against human adenovirus infection in the permissive Syrian hamster model.

Human adenoviruses can cause serious, disseminated infections in immunocompromised patients. For pediatric allogeneic stem cell transplant patients, the case fatality rate can reach 80%. Still, there is no available antiviral drug that is specifically approved by the Food and Drug Administration for the treatment of adenovirus infections. To fill this pressing medical need, we have developed NPP-669, a prodrug of cidofovir with broad activity against double-stranded DNA viruses, including adenoviruses. Here, we report on the in vivo anti-adenoviral efficacy of NPP-669. Using the immunosuppressed Syrian hamster as the model, we show that NPP-669 is highly efficacious when dosed orally at 1 mg/kg and 3 mg/kg. In a delayed administration experiment, NPP-669 was more effective than brincidofovir, a similar compound that reached Phase III clinical trials. Furthermore, parenteral administration of NPP-669 increased its efficacy approximately 10-fold compared to oral dosing without apparent toxicity, suggesting that this route may be preferable in a hospital setting. Based on these findings, we believe that NPP-669 is a promising new compound that needs to be further investigated.

Treatment and Vaccination for Smallpox and Monkeypox.

The smallpox infection with the variola virus was one of the most fatal disorders until a global eradication was initiated in the twentieth century. The last cases were reported in Somalia 1977 and as a laboratory infection in the UK 1978; in 1980, the World Health Organization (WHO) declared smallpox for extinct. The smallpox virus with its very high transmissibility and mortality is still a major biothreat, because the vaccination against smallpox was stopped globally in the 1980s. For this reason, new antivirals (cidofovir, brincidofovir, and tecovirimat) and new vaccines (ACAM2000, LC16m8 and Modified Vaccine Ankara MVA) were developed. For passive immunization, vaccinia immune globulin intravenous (VIGIV) is available. Due to the relationships between orthopox viruses such as vaccinia, variola, mpox (monkeypox), cowpox, and horsepox, the vaccines (LC16m8 and MVA) and antivirals (brincidofovir and tecovirimat) could also be used in the mpox outbreak with positive preliminary data. As mutations can result in drug resistance against cidofovir or tecovirimat, there is need for further research. Further antivirals (NIOCH-14 and ST-357) and vaccines (VACΔ6 and TNX-801) are being developed in Russia and the USA. In conclusion, further research for treatment and prevention of orthopox infections is needed and is already in progress. After a brief introduction, this chapter presents the smallpox and mpox disease and thereafter full overviews on antiviral treatment and vaccination including the passive immunization with vaccinia immunoglobulins.

Intralesional cidofovir vs. bevacizumab for recurrent respiratory papillomatosis: a systematic review and indirect meta-analysis.

BACKGROUND: Specific HPV types cause recurrent respiratory papillomatosis (R.R.P.). When administered intralesionally, cidofovir, an antiviral agent, has shown favorable outcomes in reducing papilloma. Bevacizumab, an angiogenesis inhibitor, has demonstrated improved R.R.P. However, both treatments lack FDA approval for R.R.P. Our study aims to evaluate the efficacy and safety of intralesional Cidofovir and Bevacizumab for R.R.P. and compare the two interventions. METHODS: We searched five electronic databases to find relevant studies. After the screening, data were extracted from the included studies. Pooled ratios with 95% confidence intervals (CIs) were used for categorical outcomes, and mean difference (MD) was used for continuous outcomes. Statistical heterogeneity was evaluated using the chi-squared test for I2 statistics. The Cochrane Risk of Bias assessment tool was used to assess the methodological quality of randomized controlled trials (RCTs), while the National Institutes of Health's tool was used for observational studies. Analysis was done by Review Manager software. RESULTS: In our comprehensive meta-analysis of 35 articles involving 836 patients, cidofovir demonstrated an overall remission ratio of (0.90 [95% CI: 0.83, 0.98], p = 0.01), while bevacizumab (0.92 [95% CI: 0.79, 1.07]), p = 0.3). The complete remission ratio for cidofovir was (0.66 [95% CI: 0.57, 0.75], p > 0.0001), while bevacizumab was (0.29 [95% CI: 0.12, 0.71], p = 0.07). In partial remission, Bevacizumab showed a higher ratio than Cidofovir 0.74 [0.55, 0.99] vs. 0.40 [0.30, 0.54]. Bevacizumab had a pooled ratio of 0.07 [95% CI: 0.02, 0.30] in terms of no remission, indicating better outcomes compared to Cidofovir with a ratio of 0.28 [95% CI: 0.16, 0.51]. Additionally, Cidofovir showed a favorable decrease in the Derkay Severity Score (DSS) with a mean difference (MD) of 1.98 [95% CI: 1.44, 2.52]. CONCLUSION: Cidofovir had a higher impact on complete remission compared to Bevacizumab. Both showed partial remission, with Bevacizumab having a higher ratio. Moreover, Cidofovir showed a significant decrease in DSS. Bevacizumab had lower rates of no remission and recurrence and fewer adverse events compared to Cidofovir. However, the difference between the two treatments was not significant, except for partial remission.

Monkeypox: Virology, laboratory diagnosis and therapeutic approach.

Monkeypox infection outbreaks have been observed sporadically in Africa, usually as a result of interaction with wildlife reservoirs. The genomes of the new strain range in size from 184.7 to 198.0 kb and are identified with 143-214 open reading frames. Viral cores are rapidly carried on microtubules away from the cell's perimeter and deeper into the cytoplasm once the virus and cell membranes fuse. Depending on the kind of exposure, patients with monkeypox may experience a febrile prodrome 5-13 days after exposure, which frequently includes lymphadenopathy, malaise, headaches, and muscle aches. A different diagnostic approach is available for monkeypox, including histopathological analysis, electron microscopy, immunoassays, polymerase chain reaction, genome sequencing, microarrays, loop-mediated isothermal amplification technology and CRISPR (i.e., "clustered regularly interspaced short palindromic repeats"). There are currently no particular, clinically effective treatments available for the monkeypox virus. An initial treatment is cidofovir. As a monophosphate nucleotide analog, cidofovir is transformed into an inhibitor of viral DNA polymerase by cellular kinases, which is analogous to cidofovir's function in inhibiting viral DNA synthesis. The European Medicine Agency and the Food and Drug Administration have both granted permission for IMVAMUNE, a replication-deficient, attenuated third-generation modified vaccinia Ankara vaccine, to be used for the prevention of smallpox and monkeypox in adults.

Monkeypox outbreak 2022: What we know so far and its potential drug targets and management strategies.

Monkeypox is a rare zoonotic disease caused by infection with the monkeypox virus. The disease can result in flu-like symptoms, fever, and a persistent rash. The disease is currently spreading throughout the world and prevention and treatment efforts are being intensified. Although there is no treatment that has been specifically approved for monkeypox virus infection, infected patients may benefit from using certain antiviral medications that are typically prescribed for the treatment of smallpox. The drugs are tecovirimat, brincidofovir, and cidofovir, all of which are currently in short supply due to the spread of the monkeypox virus. Resistance is also a concern, as widespread replication of the monkeypox virus can lead to mutations that produce monkeypox viruses that are resistant to the currently available treatments. This article discusses monkeypox disease, potential drug targets, and management strategies to overcome monkeypox disease. With the discovery of new drugs, it is hoped that the problem of insufficient drugs will be resolved, and it is not anticipated that drug resistance will become a major issue in the near future.

Assessment of immunomodulation and regulation of cell cycle in epithelium and stroma after Cidofovir injection in patients with recurrent respiratory papillomatosis-Pilot study.

Recurrent respiratory papillomatosis is strictly connected with human papillomavirus (HPV) infection of the epithelium of the upper respiratory tract. The main treatment of lesions located in the larynx or lower pharynx includes microsurgical excision by using a CO2 laser. To decrease the amount of surgical procedures gain in importance combined therapy with antiviral agents. The aim of this study was to investigate the effect of the intralesional application of Cidofovir on the tissue of laryngeal papillomas. We have shown that simultaneous microsurgery with adjuvant therapy of Cidofovir reduces chronic inflammation (by measuring the expression of CD4 and CD8 in tissue samples), cell proliferation, and regulates the cell cycle of HPV-infected cells by reducing the expression of p53 and p63 proteins. In addition, this strategy reduces the multiple surgical procedures and regrowth of the pathology.

Cidofovir for treating complicated monkeypox in a man with acquired immune deficiency syndrome.

In July 23, the World Health Organization (WHO) declared monkeypox (MPX) a global health emergency of international concern given its rapid spread. So far, most current MPX outbreaks have involved young men who have sex with men (MSM), although with overall mild, self-limiting clinical manifestations. We aim to describe the case of an HIV positive young MSM whose status of immune compromission probably contributed to a more severe clinical course of MPX disease, thus requiring hospitalization and antiviral treatment. He was effectively treated with Cidofovir that may be considered as a valuable component of a multi-faceted management of severe MPX.

Lack of clinical evidence of antiviral therapy for human monkeypox: A scoping review.

Since May 2022, many human monkeypox cases have been reported from non-endemic countries. This systematic review aimed to evaluate and summarize the existing research on the efficacy and safety of tecovirimat, brincidofovir, and cidofovir for patients with monkeypox. We searched studies that reported the efficacy and adverse events of tecovirimat, brincidofovir, or cidofovir for patients with human monkeypox in several databases including preprint servers. Only five studies were included. The efficacy and adverse events were assessed in only five and four patients, respectively. Regarding tecovirimat, all two patients recovered from monkeypox. One had no adverse event and the other has no description of an adverse event. Regarding brincidofovir, all three patients recovered from monkeypox but all of them had increased alanine transaminase, and one had nausea and abdominal discomfort. There was no study on treatment with cidofovir. Based on past studies and our results, tecovirimat might be the best choice due to ease of administration (oral drug), fewer side effects, and past treatment results for human monkeypox administration. However, very few studies were included in this scoping review. Therefore, further studies are needed to assess their efficacy and safety as possible treatments for human monkeypox.

Daily low dose intravesical cidofovir for the treatment of BK virus associated hemorrhagic cystitis after allogeneic stem cell transplantation.

INTRODUCTION: BK virus associated hemorrhagic cystitis(BKV-AHC) is a serious complication observed after allogeneic stem cell transplantation and the current therapeutic options are scarce with substantial renal side effects. Although the guidelines recommend intravenous cidofovir application with caution to nephrotoxicity, there are few studies which investigated intravesical administration and reported similar therapeutic results with less renal side effects. METHODS: We administered low dose, daily and consecutive (75 mg/day, for 5 days) intravesical cidofovir to 25 patients with BKV-AHC that developed after (ASCT). RESULTS: The response rate in our cohort was 92% and relapse was not encountered in 84% of the patient population during one year of follow-up. The median BK urine viral load significantly decreased from 260,000,000 IU/mL to 53,000,000 IU/mL after a week of treatment (p = 0.0001). Rise in serum creatinine was observed in 5 patients during treatment and post-treatment nephrotoxicity was seen in only 1 patient. CONCLUSIONS: Daily low dose intravesical cidofovir might be an effective treatment option for BKV-AHC after ASCT with favorable less systemic side effects.

Cidofovir in the Management of Non-Genital Warts: A Review.

INTRODUCTION: Cutaneous warts are one of the most frequent reasons for visits to the dermatologist. While there are many treatment options available and commonly used to treat warts, recurrence of lesions is common and complete clearance is rarely achieved. Cidofovir is an antiviral agent that has activity against various DNA viruses, including HPV, the virus that results in verrucae. OBJECTIVE: We examined the literature on the use of cidofovir in the treatment of non-genital warts to further assess its safety and efficacy.  Methods: A review of the literature using PubMed and Google Scholar databases was conducted to find relevant case reports and studies on the use of cidofovir in the treatment of non-genital warts.  Results: Thirteen case reports, five case series, six retrospective chart reviews, and one clinical study were reviewed and included. There were a total of 603 patients, 46.2% males and 53.7% females. Of 603 patients included in this review, 212 (35.2%) were treated with topical cidofovir for their warts. Clearance was achieved in 55.2%. There was no recurrence of lesions after clearance at two months to three years post-treatment (mean of 15.8 months). Of the 212 patients treated with topical cidofovir, 37 (17.4%) reported local side effects such as erythema, pruritus, and burning.  Discussion/Conclusion: Treatment options for recalcitrant non-genital warts are limited and have varying efficacy. Topical cidofovir may serve as an effective, safe, and affordable alternative for the clearance of recalcitrant non-genital warts, but controlled clinical trials are needed.J Drugs Dermatol. 2023;22(10):1009-1016  doi:10.36849/JDD.7258.

Evaluation of compounded cidofovir, famciclovir, and ganciclovir for the treatment of feline herpesvirus ocular surface disease in shelter-housed cats.

OBJECTIVE: To assess the efficacy of compounded cidofovir, famciclovir, and ganciclovir for the treatment of feline herpesvirus type 1 (FHV-1) ocular surface disease. ANIMALS STUDIED: 132 shelter-housed cats qPCR positive for FHV-1. PROCEDURES: A masked placebo-controlled study design was utilized. Animals were enrolled in one of four treatment groups: topical ocular placebo + oral placebo (n = 32), compounded cidofovir 0.5% ophthalmic solution + oral placebo (n = 32), compounded famciclovir oral solution (90 mg/kg) + topical ocular placebo (n = 32), and compounded ganciclovir 0.15% ophthalmic solution + oral placebo (n = 36). Cats were treated with each medication twice daily for 7 days and were evaluated on Day 1 and Day 8 using an ocular scoring system, body weight, and qPCR for FHV-1 viral load. RESULTS: Cidofovir significantly decreased viral load from Day 1 to Day 8 compared with placebo (p = .024). Neither famciclovir nor ganciclovir decreased viral load compared with placebo (p = .14, p = .41). There was no significant improvement of ocular scores for any drug group compared with placebo (p = .62). In all groups, 65%-75% of cats improved from Day 1 to Day 8. Juvenile cats had a significant increase in weight gain compared with placebo for cidofovir (p = .025) and ganciclovir (p = .023). All corneal ulcers in placebo animals failed to heal whereas 77% of ulcers in antiviral group animals healed. CONCLUSIONS: Topical ophthalmic cidofovir significantly decreased ocular FHV-1 viral shedding and increased weight gain in juvenile cats. Ganciclovir increased weight gain in juvenile cats. Compounded famciclovir demonstrated limited efficacy for the treatment of FHV-1 ocular surface disease in shelter-housed cats.

In Vitro efficacy of cyclosporine a and various antiseptics and antiviral drugs on adenovirus genotype 8, a common cause of epidemic keratoconjunctivitis.

PURPOSE: To evaluate the in vitro efficacy of cidofovir, ganciclovir, povidone-iodine, chlorhexidine, and cyclosporine A on adenovirus genotype 8. METHODS: Conjunctival samples were collected from patients with adenoviral conjunctivitis and cultured in A549 cells. Adenovirus diagnosis was confirmed by RT-PCR. For each drug, the 50% cytotoxic concentration (CC 50 ) was determined. Subsequently, the antiviral activity was tested at concentrations below CC 50, and the 50% inhibitor concentration (IC 50 ) of drugs was determined RESULTS: While the IC 50 of cidofovir against adenovirus genotype 8 was 3.07 ± 0.8 µM, ganciclovir, povidone-iodine, chlorhexidine, and cyclosporine A were not found to be effective against adenovirus genotype 8 at concentrations below the CC 50 value. CONCLUSIONS: Cidofovir was found effective and the IC 50 value was within the ranges in the literature. Ganciclovir and cyclosporine A were found to be ineffective at doses below the cytotoxic dose, povidone-iodine and chlorhexidine was found to be highly cytotoxic.

Genotypic and Phenotypic Study of Antiviral Resistance Mutations in Refractory Cytomegalovirus Infection.

BACKGROUND: This study describes the genotypic and phenotypic characterization of novel human cytomegalovirus (HCMV) genetic variants of a cohort of 94 clinically resistant HCMV patients. METHODS AND RESULTS: Antiviral-resistant mutations were detected in the UL97, UL54, and UL56 target genes of 25 of 94 (26.6%) patients. The genotype-phenotype correlation study resolved the status of 5 uncharacterized UL54 deoxyribonucleic acid polymerase (G441S, A543V, F460S, R512C, A928T) and 2 UL56 terminase (F345L, P800L) mutations found in clinical isolates. A928T conferred high, triple resistance to ganciclovir, foscarnet, and cidofovir, and A543V had 10-fold reduced susceptibility to cidofovir. Viral growth assays showed G441S, A543V, F345L, and P800L impaired viral growth capacities compared with wild-type AD169 HCMV. Three-dimensional modeling predicted A543V and A928T phenotypes but not R512C, reinforcing the need for individual characterization of mutations by recombinant phenotyping. CONCLUSIONS: Extending mutation databases is crucial to optimize treatments and to improve the assessment of patients with resistant/refractory HCMV infection.

Novel mutations in antiviral multiresistant HSV-2 genital lesion: A case report.

HSV-2 antiviral resistance mainly occurs in immunocompromised patients and especially in HIV-positive individuals receiving long-term antiviral treatment. Those situations can be challenging as few alternatives are available for HSV infection management. To describe clinical and virological significance of two novel potential HSV-2 resistance mutations after treating an obese patient with a pseudotumoral genital HSV-related lesion. Consecutive different antiviral treatments were used: valacyclovir (VACV) then foscarnet (FOS) then topical cidofovir (CDV) and finally imiquimod. Under VACV, genotypic resistance testing revealed a novel mutation within viral thymidine kinase (TK, gene UL23) not previously reported but probably accounting for antiviral resistance: W89G, similar to W88R mutation reported in HSV-1 TK, known to be associated with ACV resistance for HSV-1. Under FOS, while initial mutations were still present, a second genotypic resistance testing performed on persisting lesions showed a novel mutation within viral DNA polymerase (DNA pol, gene UL30): C625R. All three antivirals used in this case are small molecules and pharmacokinetics of VACV, FOS, and CDV have not been evaluated in animals and there are very few studies in human. As small molecules are poorly bound to proteins and distribution volume is increased in obese patients, there is risk of underdosage. This mechanism is suspected to be involved in emergence of resistance mutation and further data is needed to adapt, closely to patient profile, antiviral dosage. This report describes a chronic HSV-2 genital lesion, with resistance to current antivirals and novel mutations within viral TK and DNA pol which may confer antiviral resistance.

Cidofovir, a choice for salvage treatment of cytomegalovirus infection in patients with haploidentical hematopoietic stem cell transplantation.

BACKGROUND: Cidofovir (CDV) is a nucleotide analogue with broad antiviral activities. It remains unclear about the CDV administration for anti-cytomegalovirus (CMV) treatment in patients with haploidentical hematopoietic stem cell transplantation (haplo-HSCT). PATIENTS AND METHODS: In this study, 31 out of 101 haplo-HSCT recipients who suffered CMV infection in the CT group (conventional treatment) were enrolled into the CDV-ST group (CDV second-line treatment). These patients were treated with CDV as they failed conventional treatment or they were unavailable to the preemptive antiviral therapy. Nine patients with CMV infection were enrolled into the CDV-FT group (CDV-frontline treatment) and received CDV preemptive therapy. RESULTS: In the CDV-ST group, 23 of 28 (82.1%) patients were observed treatment response with a median time of 9 (2-23) days, and 20 (71.8%) among these patients obtained complete response (CR). In the CDV-FT group, six of eight (75.0%) patients acquired CR with a median of 6 (4-25) days. The treatment response in CDV-treated groups was comparable with those in CT groups. Besides, there was no statistical difference in CMV-related mortality between the three groups (p > .05). During the follow-up period (median follow-up:10 [1-28] months), a total of 8 of 22 (36.4%) patients experienced CMV reactivation in the CDV-ST group versus 23 of 62 (37.1%) in the CT group (p > .05). CDV-related toxicities occurred in 13 of 40 (32.5%) patients, including six (15%) reversible nephrotoxicity. CONCLUSION: Our study suggests that CDV is potentially an option for the salvage treatment of CMV infection in the haplo-HSCT patients.

Intra-host diversity of drug-resistant cytomegalovirus: A case report of cytomegalovirus infection after allogeneic hematopoietic cell transplantation.

Cytomegalovirus (CMV) is a major infectious agent causing severe complications in allogeneic hematopoietic cell transplantation (HCT) recipients, thereby warranting the need for aggressive preemptive or targeted antiviral therapy. However, prolonged or repeated use of antiviral agents, such as ganciclovir (GCV), foscarnet (FOS), and cidofovir (CDV), can result in drug-resistant CMV infection, posing challenges to successful outcomes. Here, we report a case of a patient with acute myeloid leukemia and drug-resistant CMV infection who presented with persistent CMV DNAemia, colitis, pneumonia, and encephalitis. An intra-host diversity of UL97 and UL54 mutations were detected through the genotypic resistance testing conducted on two blood samples (D+199 and D+224) and a cerebrospinal fluid (CSF) specimen (D+260) collected from the patient. UL97 L595W/L595F and L595W mutations were detected in the blood and CSF samples, respectively, that conferred GCV resistance. UL54 F412L mutation detected in all three samples conferred GCV/CDV resistance. However, the V787L mutation of UL54, conferring GCV/FOS resistance, was observed only in the D+224 blood sample. Despite combination therapy with FOS and high dose GCV and adjunctive therapy with leflunomide, the patient died from CMV infection and multiple organ failure on D+279. Further data on resistant mutations and intra-host diversity of CMV should be accumulated to elucidate the antiviral resistance and related outcomes.

Outcomes of transplant recipients treated with cidofovir for resistant or refractory cytomegalovirus infection.

BACKGROUND: Treatment of ganciclovir-resistant (GCV-R)/refractory cytomegalovirus (CMV) infections in blood/marrow transplant (BMT) and solid organ transplant (SOT) recipients remains suboptimal. Cidofovir (CDV), a nucleotide analogue with anti-CMV activity, is nephrotoxic and oculotoxic. METHODS: We retrospectively evaluated the outcomes of SOT and BMT patients with GCV-R/refractory CMV treated with CDV between 1/1/2008 and 12/31/2017. DATA COLLECTED: baseline demographics, CMV serostatus, clinical and virologic presentations and outcomes, UL97 and UL54 genotype mutations, drug toxicities, and cause of death. Descriptive statistics were used. RESULTS: 16 patients received CDV for treatment of CMV: six BMT and 10 SOT. Seven (47%) of the patients had high-risk donor/recipient serostatus: six (60%) SOT were D+/R-; one (16.7%) BMT was D-/R+. Median time to CMV DNAemia was 131 days post-transplant (IQR, 37.5-230.3). Proven tissue invasive disease was present in three patients (18.8%). Twelve (75%) had genotype testing; 10 (83.3%) of those had antiviral resistance mutations. While on CDV, six (37.5%) developed nephrotoxicity, and four (25%) developed uveitis (two had both uveitis and nephrotoxicity). Eight (50%) had failure to clear CMV DNAemia despite CDV treatment. Eight (50%) of the patients died; median time to death, after initiation of CDV, was 33.5 days [IQR22-988]. CONCLUSIONS: In the absence of good therapeutic alternatives, CDV is used in GCV-R/refractory CMV infection. However, it is associated with a substantial risk of toxicity and failure to clear CMV DNAemia, highlighting the need for development of newer and less toxic therapies. The high mortality in this group of patients underscores the severity of illness in this population.

Adenovirus: Epidemiology, Global Spread of Novel Types, and Approach to Treatment.

Adenoviruses (AdVs) are DNA viruses that typically cause mild infections involving the upper or lower respiratory tract, gastrointestinal tract, or conjunctiva. Rare manifestations of AdV infections include hemorrhagic cystitis, hepatitis, hemorrhagic colitis, pancreatitis, nephritis, or meningoencephalitis. AdV infections are more common in young children, due to lack of humoral immunity. Epidemics of AdV infection may occur in healthy children or adults in closed or crowded settings (particularly military recruits). The vast majority of cases are self-limited. However, the clinical spectrum is broad and fatalities may occur. Dissemination is more likely in patients with impaired immunity (e.g., organ transplant recipients, human immunodeficiency virus infection). Fatality rates for untreated severe AdV pneumonia or disseminated disease may exceed 50%. More than 100 genotypes and 52 serotypes of AdV have been identified and classified into seven species designated HAdV-A through -G. Different types display different tissue tropisms that correlate with clinical manifestations of infection. The predominant types circulating at a given time differ among countries or regions, and change over time. Transmission of novel strains between countries or across continents and replacement of dominant viruses by new strains may occur. Treatment of AdV infections is controversial, as prospective, randomized therapeutic trials have not been done. Cidofovir has been the drug of choice for severe AdV infections, but not all patients require treatment. Live oral vaccines are highly efficacious in reducing the risk of respiratory AdV infection and are in routine use in the military in the United States but currently are not available to civilians.

[Successful treatment with cidofovir for disseminated adenovirus infection accompanied by hemophagocytic syndrome and meningitis in an allogeneic hematopoietic stem cell transplantation recipient].

A 65-year-old woman received bone marrow transplantation from an HLA-DRB1 one locus mismatched donor for high-risk myelodysplastic syndrome. On day 237 after transplantation, she developed recurrent acute gastrointestinal graft-versus-host disease and adenoviral hemorrhagic cystitis. Hence, the methylprednisolone (mPSL) dose was increased to 2 mg/kg, and mesenchymal stem cells were administered. After the dose was tapered, she developed high fever, gross hematuria, and progressive pancytopenia. Then, the serum LDH, ferritin, and hepatobiliary enzyme levels of the patient increased, and hemophagocytosis was observed based on bone marrow examination. The adenovirus DNA level in the plasma was 6.3×106 copies/ml on day 278, and the volume of cerebrospinal fluid increased. Hence, the patient was diagnosed with meningitis and disseminated adenovirus infection. On day 288, cidofovir was administered at a dose of 1 mg/kg three times a week for 8 doses. The mPSL dose was again increased to 2 mg/kg for the treatment of hemophagocytic syndrome. Then, the patient's symptoms gradually improved, and the adenovirus viral load became negative on day 369. Based on the clinical course of our patient, cidofovir is useful for severe adenovirus infection.