Serial PCR Research Articles

The CoLab score is associated with SARS-CoV-2 viral load during admission in individuals admitted to the intensive care unit: the CoLaIC cohort study.

The present study examines the temporal association between the changes in SARS-CoV-2 viral load during infection and whether the CoLab-score can facilitate de-isolation. Nasal swabs and blood samples were collected from ICU-admitted SARS-CoV-2 positive patients at Maastricht UMC+ from March 25, 2020 to October 1, 2021. The CoLab-score was calculated based on 10 blood parameters and age and can range from-43 to 6. Three mixed effects analyses compared patient categories based on initial PCR Ct values (low; Ct≤20, mid; 20>Ct≤30, high; Ct>30), serial PCR Ct values to CoLab-scores over time, and the association between within-patient delta Ct values and CoLab-scores. In 324 patients, the median Ct was 33, and the median CoLab-score was-1.78. Mid (n=110) and low (n=41) Ct-categories had higher CoLab-scores over time (+0.60 points, 95 % CI; 0.04-1.17, and +0.28 points, 95 % CI-0.49 to 1.04) compared to the high Ct (n=87) category. Over time, higher serial Ct values were associated with lower serial CoLab-scores, decreasing by-0.07 points (95 % CI;-0.11 to-0.02) per day. Increasing delta Ct values were associated with a decreasing delta CoLab-score of-0.12 (95 % CI;-0.23;-0.01). The study found an association between lower viral load on admission and reduced CoLab-score. Additionally, a decrease in viral load over time was associated with a decrease in CoLab-score. Therefore, the CoLab-score may make patient de-isolation an option based on the CoLab-score.

Parasitemia and antibody response to benznidazole treatment in a cohort of patients with chronic Chagas disease

BackgroundEvaluating the effectiveness of Chagas disease treatment poses challenges due to the lack of biomarkers for disease progression and therapeutic response. In this study, we aimed to assess the clearance of Trypanosoma cruzi (T. cruzi) parasites in a group of benznidazole (BNZ)-treated chronic Chagas disease patients using high-sensitivity quantitative PCR (qPCR) and track T. cruzi antibody levels through a semiquantitative chemiluminescent assay.MethodsA total of 102 T. cruzi seropositive patients with previous PCR-positive results were enrolled in the study. We collected samples 30 days before treatment (T-30d), on the day before initiating BNZ treatment (T0d), and at follow-up visits 60 days (T60d), 6 months (T6M), 12 months (T12M), and 36 months (T36M) after treatment initiation. Treatment efficacy was assessed by testing of serial samples using a target-capture qPCR assay specific to satellite T. cruzi DNA and the ORTHO T. cruzi ELISA Test System for antibody quantitation.ResultsOf the enrolled individuals, 87 completed at least 50% of the treatment course, and 86 had PCR results at follow-up visits T6M, T12M, and T36M. PCR results exhibited fluctuations before and after treatment, but levels were significantly lower post-treatment. Only 15 cases consistently tested PCR-negative across all post-treatment visits. Notably, nearly all participants demonstrated a declining antibody trajectory, with patients who tested PCR-negative at T36M exhibiting an earlier and more pronounced decline compared to PCR-positive cases at the same visit.ConclusionOur study suggests that serial PCR results pose challenges in interpretation. In contrast, serial antibody levels may serve as an ancillary, or even a more reliable indicator of parasite decline following BNZ treatment. Monitoring antibody levels can provide valuable insights into the efficacy of treatment and the persistence of parasites in Chagas disease patients.

Early Changes in Circulating Cell-Free KRAS G12C Predict Response to Adagrasib in KRAS Mutant Non-Small Cell Lung Cancer Patients.

Non-invasive monitoring of circulating tumor DNA (ctDNA) has the potential to be a readily available measure for early prediction of clinical response. Here, we report on early ctDNA changes of KRAS G12C in a Phase 2 trial of adagrasib in patients with advanced, KRAS G12C-mutant lung cancer. We performed serial droplet digital PCR (ddPCR) and plasma NGS on 60 KRAS G12C-mutant patients with lung cancer that participated in cohort A of the KRYSTAL-1 clinical trial. We analyzed the change in ctDNA at 2 specific intervals: Between cycles 1 and 2 and at cycle 4. Changes in ctDNA were compared with clinical and radiographic response. We found that, in general, a maximal response in KRAS G12C ctDNA levels could be observed during the initial approximately 3-week treatment period, well before the first scan at approximately 6 weeks. 35 patients (89.7%) exhibited a decrease in KRAS G12C cfDNA >90% and 33 patients (84.6%) achieved complete clearance by cycle 2. Patients with complete ctDNA clearance at cycle 2 showed an improved objective response rate (ORR) compared with patients with incomplete ctDNA clearance (60.6% vs. 33.3%). Furthermore, complete ctDNA clearance at cycle 4 was associated with an improved overall survival (14.7 vs. 5.4 months) and progression-free survival (HR, 0.3). These results support using early plasma response of KRAS G12C assessed at approximately 3 weeks to anticipate the likelihood of a favorable objective clinical response.

Risk factors and vectors for SARS-CoV-2 household transmission: a prospective, longitudinal cohort study

Despite circumstantial evidence for aerosol and fomite spread of SARS-CoV-2, empirical data linking either pathway with transmission are scarce. Here we aimed to assess whether the presence of SARS-CoV-2 on frequently-touched surfaces and residents' hands was a predictor of SARS-CoV-2 household transmission. In this longitudinal cohort study, during the pre-alpha (September to December, 2020) and alpha (B.1.1.7; December, 2020, to April, 2021) SARS-CoV-2 variant waves, we prospectively recruited contacts from households exposed to newly diagnosed COVID-19 primary cases, in London, UK. To maximally capture transmission events, contacts were recruited regardless of symptom status and serially tested for SARS-CoV-2 infection by RT-PCR on upper respiratory tract (URT) samples and, in a subcohort, by serial serology. Contacts' hands, primary cases' hands, and frequently-touched surface-samples from communal areas were tested for SARS-CoV-2 RNA. SARS-CoV-2 URT isolates from 25 primary case-contact pairs underwent whole-genome sequencing (WGS). From Aug 1, 2020, until March 31, 2021, 620 contacts of PCR-confirmed SARS-CoV-2-infected primary cases were recruited. 414 household contacts (from 279 households) with available serial URT PCR results were analysed in the full household contacts' cohort, and of those, 134 contacts with available longitudinal serology data and not vaccinated pre-enrolment were analysed in the serology subcohort. Household infection rate was 28·4% (95% CI 20·8-37·5) for pre-alpha-exposed contacts and 51·8% (42·5-61·0) for alpha-exposed contacts (p=0·0047). Primary cases' URT RNA viral load did not correlate with transmission, but was associated with detection of SARS-CoV-2 RNA on their hands (p=0·031). SARS-CoV-2 detected on primary cases' hands, in turn, predicted contacts' risk of infection (adjusted relative risk [aRR]=1·70 [95% CI 1·24-2·31]), as did SARS-CoV-2 RNA presence on household surfaces (aRR=1·66 [1·09-2·55]) and contacts' hands (aRR=2·06 [1·57-2·69]). In six contacts with an initial negative URT PCR result, hand-swab (n=3) and household surface-swab (n=3) PCR positivity preceded URT PCR positivity. WGS corroborated household transmission. Presence of SARS-CoV-2 RNA on primary cases' and contacts' hands and on frequently-touched household surfaces associates with transmission, identifying these as potential vectors for spread in households. National Institute for Health Research Health Protection Research Unit in Respiratory Infections, Medical Research Council.

Evaluation of Correctional Facility COVID-19 Outbreaks With Layered Mitigation Strategies Including Vaccination: Colorado, 2020-2021.

In 2020-2021, a Colorado corrections facility experienced four COVID-19 outbreaks. Case counts, attack rates (ARs) in people who are detained or incarcerated (PDI), and mitigation measures used in each outbreak were compared to evaluate effects of combined strategies. Serial PCR testing, isolation/quarantine, and masking were implemented in outbreak 1. Daily staff antigen testing began in outbreak 2. Facility-wide COVID-19 vaccination started in outbreak 3 and coverage increased by the end of outbreak 4 (PDI: <1% to 59%, staff: 27% to 40%). Despite detection of variants of concern, outbreaks 3 and 4 had 97% lower PDI ARs (both 1%) than outbreak 2 (29%). Daily staff testing and increasing vaccination coverage, with other outbreak mitigation strategies, are important to reduce COVID-19 transmission in congregate settings.

‘Dynamic zero-COVID’ policy and viral clearance during an omicron wave in Tianjin, China: a city-wide retrospective observational study

ObjectiveTo report how the Chinese mainland battled its first omicron wave, which happened in Tianjin, a metropolis with 14 million residents. We also sought to better understand how clinical features...

S1752 Infiltration of the Biliary Tract With Cytomegalovirus

Introduction: Cytomegalovirus (CMV) is known to affect immunosuppressed patients. CMV causes infections in post-transplant and HIV/AIDS patients but also those with advanced age or hematologic malignancies. This case presents CMV infiltration of the biliary tract in an elderly patient with 2 hematologic malignancies. Case Description/Methods: A 74-year-old male with tobacco use and chronic alcohol abuse was undergoing evaluation for anemia and thrombocytopenia. EGD and colonoscopy were unremarkable. Bone marrow biopsy revealed myelodysplastic syndrome (MDS) and B cell lymphoma. He subsequently developed jaundice. Labs revealed a total bilirubin of 10.4, ALP 1077, AST 107 and ALT 131. Viral hepatitis panel and HIV were negative. MRCP showed a dilated CBD and a filling defect within the CHD extending to the left hepatic duct with contour irregularity and narrowing in the left hepatic duct giving a beaded appearance. ERCP demonstrated a dilated CBD and CHD in addition to mild left and right hepatic duct dilatation with no definitive strictures or filling defects. A plastic bile duct stent was placed due to poor drainage of contrast. His LFTs continued to remain elevated. Liver biopsy revealed moderate cholestasis, sinusoidal dilatation, mild portal inflammation, biliary metaplasia, and stage 2 fibrosis. Repeat MRCP showed worsening intrahepatic and extrahepatic biliary dilatation with no further filling defect. ERCP with cholangioscopy was then performed. Bile duct mucosa had diffuse superficial granular like appearance in the common duct and main hepatic branches, which did not resemble typical previous biliary stent inflammatory changes. Biopsies of the bile duct were obtained. A fully covered metal stent was placed for further biliary drainage due to persistent poor contrast drainage. Bile duct pathology showed chronic active inflammation with CMV viral inclusions in the hepatic hilum and left hepatic takeoff. CMV PCR from the biliary specimen was positive. Blood CMV IgG was positive. Blood CMV PCR and CMV IgM were negative. His liver enzymes showed improvement after a fully covered stent was placed. He was started on a 2 week course of valganciclovir, with serial blood CMV PCR monitoring while on Rituximab for his B cell lymphoma. Discussion: This patient’s immunosuppression secondary to MDS, B cell lymphoma and advanced age increased his risk of a CMV infection with bile duct involvement. Cholangioscopy can aid in viewing subtle bile duct irregularities with biopsies to assess for CMV involvement.

Linked nosocomial COVID-19 outbreak in three facilities for people with intellectual and developmental disabilities due to SARS-CoV-2 variant B.1.1.519 with spike mutation T478K in the Netherlands

BackgroundIndividuals with intellectual and developmental disabilities (IDD) living in congregated settings have increased risk of COVID-19 infection and mortality. Little is known about variant B.1.1.519 with spike mutation T478K, dominant in Mexico. We describe a linked SARS-CoV-2 B.1.1.519 outbreak in three IDD facilities in the Netherlands.MethodsFollowing notification of the index, subsequent cases were identified through serial PCR group testing. Positive specimens were submitted for whole-genome-sequencing. Clinical information was gathered through interviews with staff members of the three facilities.ResultsAttack rate (AR) in clients of the index facility was 92% (23/25), total AR in clients 45% (33/73) and in staff members 24% (8/34). 55% (18/33) of client cases were asymptomatic, versus 25% (2/8) of staff members. Five client cases (15%) were hospitalized, two died (6%). Sequencing yielded the same specific B.1.1.519 genotype in all three facilities. No significant difference in median viral load was established comparing the B.1.1.519 variant with other circulating variants. The index of the linked outbreak reported no travel history or link to suspected or confirmed cases suggesting regional surveillance. Observed peak regional prevalence of B.1.1.519 during the outbreak supports this.ConclusionAR, morbidity and mortality prior to control measures taking effect were high, probably related to the specific characteristics of the IDD setting and its clients. We assessed no evidence for intrinsic contributing properties of variant B.1.1.519. Our study argues for enhanced infection prevention protocols in the IDD setting, and prioritization of this group for vaccination against COVID-19.

One-step and sequential SARSCOV-2 polymerase chain reaction tests would not work every time.

IntroductionRT‐PCR is widely used as a diagnostic test for the detection of SARS‐CoV‐2. In this study, we aim to describe the clinical utility of serial PCR testing in the final detection of COVID‐19.MethodWe collected multiple nasopharyngeal swab samples from patients who had negative RT‐PCR test on the first day after hospitalization. RT‐PCR tests were performed on the second day for all patients with initial negative result. For the patients with secondary negative results on day 2, tertiary RT‐PCR tests were performed on day 3 after hospitalization.ResultAmong 68 patients with initial negative test results, at the end of follow‐up, the mortality number was 20 (29.4%). About 33.8% of patients had subsequent positive PCR test results for the second time and 17.4% of the patients who performed third PCR test had positive result.ConclusionBased on this study, serial RT‐PCR testing is unlikely to yield additional information.

Viral Culture in Hospitalized Congregate Care Patients With Prolonged SARS-CoV-2 Viral RNA Detection

Prolonged detection of SARS-CoV-2 viral RNA has been observed in hospitalized congregate care patients following resolution of clinical symptoms. It is unknown whether patients with persistent PCR positivity pose a risk for COVID-19 transmission. The purpose of this study was to examine the results of serial PCR testing, viral load, and viral culture in patients awaiting discharge prior to a negative PCR test. We sampled 14 patients who were admitted from skilled nursing and/or rehabilitation facilities to a large academic medical center, had clinical signs and symptoms of COVID-19, and had multiple PCR-positive tests separated by at least 14 days. PCR-positive nasopharyngeal swabs were obtained from each patient for viral load quantification and viral culture. The mean age of patients was 72.5 years (55 – 92), with a mean peak SOFA score of 5.6 (1 – 11). Patients were hospitalized for a mean of 37.0 days (25 – 60). RNA was detected by PCR for a mean of 32.9 days (19 – 47). Mean viral load for the first PCR-positive nasopharyngeal swab collected at our hospital was 5.81 genomic copies/mL (2.12 – 9.72). Viral load decreased significantly with days from clinical symptom onset (R = -0.69, 95% CI, -0.80 – -0.55). Four out of 28 samples grew active virus via culture, with no active virus isolates after 2 days of symptom onset. Our viral culture data suggests that persistent PCR positivity may not correlate with infectivity, which has important implications for COVID-19 infection control precautions among older congregate care patients.

An observational study of breakthrough SARS-CoV-2 Delta variant infections among vaccinated healthcare workers in Vietnam.

BackgroundData on breakthrough SARS-CoV-2 Delta variant infections in vaccinated individuals are limited.MethodsWe studied breakthrough infections among Oxford-AstraZeneca vaccinated healthcare workers in an infectious diseases hospital in Vietnam. We collected demographic and clinical data alongside serial PCR testing, measurement of SARS-CoV-2 antibodies, and viral whole-genome sequencing.FindingsBetween 11th–25th June 2021 (7-8 weeks after the second dose), 69 staff tested positive for SARS-CoV-2. 62 participated in the study. Most were asymptomatic or mildly symptomatic and all recovered. Twenty-two complete-genome sequences were obtained; all were Delta variant and were phylogenetically distinct from contemporary viruses obtained from the community or from hospital patients admitted prior to the outbreak. Viral loads inferred from Ct values were 251 times higher than in cases infected with the original strain in March/April 2020. Median time from diagnosis to negative PCR was 21 days (range 8–33). Neutralizing antibodies (expressed as percentage of inhibition) measured after the second vaccine dose, or at diagnosis, were lower in cases than in uninfected, fully vaccinated controls (median (IQR): 69.4 (50.7-89.1) vs. 91.3 (79.6-94.9), p=0.005 and 59.4 (32.5-73.1) vs. 91.1 (77.3-94.2), p=0.002). There was no correlation between vaccine-induced neutralizing antibody levels and peak viral loads or the development of symptoms.InterpretationBreakthrough Delta variant infections following Oxford-AstraZeneca vaccination may cause asymptomatic or mild disease, but are associated with high viral loads, prolonged PCR positivity and low levels of vaccine-induced neutralizing antibodies. Epidemiological and sequence data suggested ongoing transmission had occurred between fully vaccinated individuals.FundingWellcome and NIH/NIAID

Safety and PCR monitoring in 161 semi-immune Kenyan adults following controlled human malaria infection.

BACKGROUNDNaturally acquired immunity to malaria is incompletely understood. We used controlled human malaria infection (CHMI) to study the impact of past exposure on malaria in Kenyan adults in relation to infection with a non-Kenyan parasite strain.METHODSWe administered 3.2 × 103 aseptic, purified, cryopreserved Plasmodium falciparum sporozoites (Sanaria PfSPZ Challenge, NF54 West African strain) by direct venous inoculation and undertook clinical monitoring and serial quantitative PCR (qPCR) of the 18S ribosomal RNA gene. The study endpoint was met when parasitemia reached 500 or more parasites per μL blood, clinically important symptoms were seen, or at 21 days after inoculation. All volunteers received antimalarial drug treatment upon meeting the endpoint.RESULTSOne hundred and sixty-one volunteers underwent CHMI between August 4, 2016, and February 14, 2018. CHMI was well tolerated, with no severe or serious adverse events. Nineteen volunteers (11.8%) were excluded from the analysis based on detection of antimalarial drugs above the minimal inhibitory concentration or parasites genotyped as non-NF54. Of the 142 volunteers who were eligible for analysis, 26 (18.3%) had febrile symptoms and were treated; 30 (21.1%) reached 500 or more parasites per μL and were treated; 53 (37.3%) had parasitemia without meeting thresholds for treatment; and 33 (23.2%) remained qPCR negative.CONCLUSIONWe found that past exposure to malaria, as evidenced by location of residence, in some Kenyan adults can completely suppress in vivo growth of a parasite strain originating from outside Kenya.TRIAL REGISTRATIONClinicalTrials.gov NCT02739763.FUNDINGWellcome Trust.

Resumption of professional football during the COVID-19 pandemic. Study findings from Iran

Due to concerns of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) transmission, professional football (soccer) was terminated almost everywhere in the world in early 2020. These are the results from a prospective cohort study conducted in Iran to analyze the resumption of professional football during the coronavirus disease 2019 (COVID-19) pandemic under assigned protocols and regulations. Sixteen teams consisting of 805 individuals formally agreed to follow the rules assigned by the ministry of health and CORONA headquarters in sport, and were subject to study monitoring. The resumption process was implemented over a 5-month period, beginning with a training phase followed by 14 match weeks of professional football. A self-declaration form was provided for the subjects to report any suspicious symptoms immediately and serial PCR testing was performed every 10 days using nasal swab samples. Those with positive tests were to be isolated until the symptoms were resolved or a negative test was returned. Of the 805 individuals included, 17.89% subjects were infected by the SARS-CoV‑2 virus (85 players and 59 staff members and officials). Only two matches were canceled in accordance with the regulations, and no severe cases were found. Case-tracing suggested that most transmissions occurred off the pitch. In conclusion, applying strict hygiene protocols and early case identification by performing repetitive PCR testing could benefit the resumption of professional football competitions.

Rapid return to normal activities at a residential summer camp during the COVID-19 pandemic

AimInfection prevention and control (IPC) within residential settings is a central focus of the coronavirus disease 2019 (COVID-19) pandemic. Youth residential summer camps are an excellent model for such environments and have thus far had mixed results. The aim of this report was to describe the successful implementation of a seven-week overnight summer camp with rapid return to normal activities from June to August 2020.Subjects and methodsThis retrospective study included 427 individuals who traveled from 24 US states. All staff and campers were tested by serial nasopharyngeal PCR tests in the context of strict infection prevention and control (IPC) measures, including cohorts and masking. The entire camp population was isolated from non-camp personnel with special measures for food, supply, and mail delivery.ResultsDuring the two-week staff session, one staff member tested positive for SARS-CoV-2, was isolated, and sent safely off premises. All other campers and staff had three negative PCR tests: 1–8 days before arrival, upon arrival, and 5–6 days after arrival. After these three negative tests, 6 days into camp, most IPCs, including masking, were successfully lifted and a normal camp experience was possible.ConclusionsThese findings indicate that serial PCR-based testing and strict adherence to IPC measures among cohorts can allow for successful assumption of near normal group activities in a residential setting during the COVID-19 pandemic. This result at an overnight summer camp has broad implications for similar residential communities such as boarding schools, other youth education and development programs, as well as nursing homes and military installations.

Effect of Remdesivir on COVID-19 PCR Positivity and Cycle Threshold in Kidney Transplant Recipients

Information regarding Coronavirus disease 2019 in the transplant population is lacking. Recently it has been suggested that cycle threshold values obtained on polymerase chain reaction tests may serve as a marker of disease severity with lower values (i.e., higher viral load) being associated with higher mortality. This study was done to assess the impact of remdesivir use on the time to a negative COVID-19 PCR as well as the degree of change between two Ct’s based on treatment. A total of 30 kidney transplant patients with a new diagnosis of COVID-19 were assessed. Serial PCR results were followed from the time of diagnosis then every 2–4 weeks until negative. In patients who received remdesivir immediately after COVID-19 confirmation compared to no remdesivir, time to negative PCR was not statistically different with a median duration of 57 days in both groups (p = 0.369). The change in the Ct between the first and the second PCR test was also not statistically different between groups with a median change of 18.4 cycles in the remdesivir group and 15.7 cycles without remdesivir (p = 0.516). The results of this small single-center analysis suggest that remdesivir may not be beneficial in shortening time to a negative COVID-19 PCR.

High variation in immune responses and parasite phenotypes in naturally acquired Trypanosoma cruzi infection in a captive non-human primate breeding colony in Texas, USA.

Trypanosoma cruzi, the causative agent of human Chagas disease, is endemic to the southern region of the United States where it routinely infects many host species. The indoor/outdoor housing configuration used in many non-human primate research and breeding facilities in the southern of the USA provides the opportunity for infection by T. cruzi and thus provides source material for in-depth investigation of host and parasite dynamics in a natural host species under highly controlled and restricted conditions. For cynomolgus macaques housed at such a facility, we used a combination of serial blood quantitative PCR (qPCR) and hemoculture to confirm infection in >92% of seropositive animals, although each method alone failed to detect infection in >20% of cases. Parasite isolates obtained from 43 of the 64 seropositive macaques were of 2 broad genetic types (discrete typing units, (DTU's) I and IV); both within and between these DTU groupings, isolates displayed a wide variation in growth characteristics and virulence, elicited host immune responses, and susceptibility to drug treatment in a mouse model. Likewise, the macaques displayed a diversity in T cell and antibody response profiles that rarely correlated with parasite DTU type, minimum length of infection, or age of the primate. This study reveals the complexity of infection dynamics, parasite phenotypes, and immune response patterns that can occur in a primate group, despite being housed in a uniform environment at a single location, and the limited time period over which the T. cruzi infections were established.

BK Virus Associated Nephropathy (BKVAN) in a Lung Transplant Recipient in the Setting of Augmented Immunosuppression

Introduction Acute kidney injury (AKI) and chronic kidney disease (CKD) are common amongst lung transplant recipients due to calcineurin inhibitor (CNI) use. We describe a case of acute BK virus associated nephropathy (BKVAN) in a lung transplant recipient with baseline CKD stage 4. Case Report A 73-year-old male status post right single lung transplant eight years prior for tobacco-induced emphysema presented for admission for acute cellular rejection (ACR). He was treated with methylprednisolone 10 mg/kg x three days per protocol. His renal function was within normal range pre-transplant, but had gradually progressed to CKD 4 with a new baseline creatinine of 2.4 at time of admission. Progressive CKD was attributed to CNIs. He had been placed on a CNI sparing regimen with everolimus more than one year prior to index admission with continued progression of renal dysfunction. Upon initiation of methylprednisolone, creatinine began to rise and eventually peaked to 4.3. UA showed trace protein but was otherwise bland, urine microscopy with muddy brown granular casts and renal tubular epithelial (RTE) cells. Renal ultrasound was poor quality showing possible small right kidney, left kidney not imaged. As part of his work-up, a BK virus PCR from his urine was sent and positive, with greater than 162 million IU/mL: serum BK PCR returned at 146,000 IU/mL. Microscopic urine analysis demonstrated RTE cells consistent with decoy cells, supportive of viral injury. A kidney biopsy was considered, however not performed because of chronic anticoagulation for a recent history of venous thromboembolism. Over the next several days, creatinine decreased minimally to 3.76. Patient was discharged home with outpatient nephrology follow up and had serial serum BK PCR tests for disease monitoring.In the setting of declining pulmonary function testing and ACR, we were unable to decrease immunosuppression without risking further deterioration of the lung allograft. Summary To our knowledge, this is the ninth reported case of BKVAN after lung transplant. BK viremia and BKVAN are likely an under-diagnosed etiology of CKD and AKI in the lung transplant population. We speculate that our patient had undiagnosed low level BK viremia that was affecting his renal function chronically, but when treated with high dose steroids, led to an acute BK nephropathy.

Usefulness of PCR for Trypanosoma cruzi DNA in blood and endomyocardial biopsies for detection of Chagas disease reactivation after heart transplantation: A comparative study.

Chagas disease reactivation (CDR) after heart transplantation is characterized by relapse of the infectious disease with proliferation and dissemination of Trypanosoma cruzi parasites. Serial blood PCR testing is consensually recommended for CDR monitoring, but there is uncertainty about the incremental value in performing the molecular tests in endomyocardial biopsies (EMB). We compared qualitative and quantitative results of PCR for T cruzi DNA in 62 pairs of blood and EMB collected with a maximum time interval of 7days, from 34 heart-transplanted, chagasic patients. Blood PCR resulted positive in 39/62 (62.9%) samples, with PL ranging from 0.14 to 1610.73 (median: 3.31). PCR resulted positive in 8/60 (13.3%) EMB, with PL ranging from 2.82 to 1670.55 (median: 65.63). All blood samples which tested negative presented a paired EMB which also tested negative. However, 31/39 (79.5%) blood samples which tested positive presented a paired EMB which tested negative. There was poor agreement between blood and EMB PCR (kappa=0.153). CDR affecting the myocardium (myo-CDR) was diagnosed in three occasions. PCR resulted positive in both blood and EMB at the time of myo-CDR, with PL ranging from 0.61 to 1610.73 in blood and 13.8 to 1670.55 in EMB. Negative PCR for T cruzi in blood rules out myo-CDR, with no value of testing EMB. Positive PCR in blood with high PL is diagnostic for myo-CDR. If PCR in blood results positive with low PL, testing EMB is useful: negative PCR turns unlikely, and positive PCR reinforces greatly the possibility of myo-CDR.

Discontinuation of Maintenance Tyrosine Kinase Inhibitors in Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia outside of Transplant

Background: The addition of tyrosine kinase inhibitors (TKIs) to chemotherapy has dramatically improved outcomes of patients with Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL). When allogeneic hematopoietic stem cell transplant (HSCT) is performed, maintenance TKI is generally given for a fixed duration. However, the optimal duration of TKI outside of HSCT remains unknown, and the common practice is to continue indefinitely. Here, we report characteristics and outcomes of 9 patients treated with chemotherapy + TKI without HSCT and later discontinued TKI. Methods: Among 188 patients with Ph-positive ALL who did not undergo HSCT, 9 of them discontinued maintenance TKI mainly due to side effects. Patients were closely monitored with serial PCR testing for the BCR-ABL1 transcript. Major molecular response (MMR) was defined as BCR-ABL1 transcript ≤0.1% on the international scale for p210 transcripts and a 3-log reduction from baseline for p190 transcripts. Deep molecular remission (DMR) was defined as the absence of quantifiable BCR-ABL1 transcripts with a sensitivity of 0.01%. Molecular relapse was defined as loss of MMR. Treatment-free remission (TFR) was defined from time of TKI discontinuation to molecular relapse, last follow-up, or death from any cause. Results: At the time of TKI discontinuation, transcript level was undetected in 6 patients, <0.01% in 2 patients, and 0.01% in another patient. Prior to discontinuation, the median duration of TKI therapy and of DMR was 70 and 47 months, respectively. No morphological relapse occurred. Three patients (33%) had molecular relapse at a median of 6 months. All 3 resumed TKI therapy, and 2 of them regained DMR after a median of 13 months. After a median follow-up of 49 months, the median TFR was not reached, and the 4-year TFR rate was 65%. The median duration of DMR in patients with and without molecular relapse was 22 and 58 months, respectively (p = 0.096). Conclusion: TKI discontinuation outside of HSCT in Ph-positive ALL in the setting of compelling toxicity may be safe only among a highly selected group of patients with deep and prolonged DMR undergoing close and frequent monitoring. Validation of these findings in prospective clinical trials is highly needed.

Emergence of Monosomy 7 in Philadelphia-Negative Cells during MDS Development and not CML Diagnosis Proved by Serial Droplet Digital PCR

Emergence of Monosomy 7 in Philadelphia-Negative Cells during MDS Development and not CML Diagnosis Proved by Serial Droplet Digital PCR