Myelofibrosis: An unusual presentation of disseminated tuberculosis.

Disseminated tuberculosis (DTB) often presents with protean clinical manifestations that often leads to potential diagnostic dilemmas. The nonspecific features may include pyrexia of unknown origin, hepatosplenomegaly, lymphadenopathy, meningitis, and a variety of hematological abnormalities, namely anemia, pancytopenia, and leukemoid reaction. Tuberculosis is one of the nonhematopoietic diseases that has been reported in conjunction with myelofibrosis. We, hereby, report a case of DTB with massive splenomegaly, severe pancytopenia, and marrow fibrosis.

Strain-resolved microbiome sequencing reveals mobile elements that drive bacterial competition on a clinical timescale.

BACKGROUND: Populations of closely related microbial strains can be simultaneously present in bacterial communities such as the human gut microbiome. We recently developed a de novo genome assembly approach that uses read cloud sequencing to provide more complete microbial genome drafts, enabling precise differentiation and tracking of strain-level dynamics across metagenomic samples. In this case study, we present a proof-of-concept using read cloud sequencing to describe bacterial strain diversity in the gut microbiome of one hematopoietic cell transplantation patient over a 2-month time course and highlight temporal strain variation of gut microbes during therapy. The treatment was accompanied by diet changes and administration of multiple immunosuppressants and antimicrobials. METHODS: We conducted short-read and read cloud metagenomic sequencing of DNA extracted from four longitudinal stool samples collected during the course of treatment of one hematopoietic cell transplantation (HCT) patient. After applying read cloud metagenomic assembly to discover strain-level sequence variants in these complex microbiome samples, we performed metatranscriptomic analysis to investigate differential expression of antibiotic resistance genes. Finally, we validated predictions from the genomic and metatranscriptomic findings through in vitro antibiotic susceptibility testing and whole genome sequencing of isolates derived from the patient stool samples. RESULTS: During the 56-day longitudinal time course that was studied, the patient's microbiome was profoundly disrupted and eventually dominated by Bacteroides caccae. Comparative analysis of B. caccae genomes obtained using read cloud sequencing together with metagenomic RNA sequencing allowed us to identify differences in substrain populations over time. Based on this, we predicted that particular mobile element integrations likely resulted in increased antibiotic resistance, which we further supported using in vitro antibiotic susceptibility testing. CONCLUSIONS: We find read cloud assembly to be useful in identifying key structural genomic strain variants within a metagenomic sample. These strains have fluctuating relative abundance over relatively short time periods in human microbiomes. We also find specific structural genomic variations that are associated with increased antibiotic resistance over the course of clinical treatment.

Infectious complications in patients on treatment with Ruxolitinib: case report and review of the literature.

BACKGROUND: Primary myelofibrosis is a chronic myeloproliferative neoplasm that may cause debilitating symptoms, which can be improved with the use of Ruxolitinib, a Janus kinase 2 inhibitor. However, this agent has significant immunomodulatory effects which may increase the risk for infections. METHODS: We searched the literature and our institutional electronic medical record for reported cases of infections in adult patients on ruxolitinib treatment. RESULTS: We found 28 cases in our literature search and 4 cases from our Institution for a total of 32 cases. The most common infection was tuberculosis in 11/32 cases (34%), followed by cryptococcal infection in 3/32 (9%) and hepatitis B virus reactivation in 3/32 (9%). CONCLUSION: Opportunistic infections associated with ruxolitinib use are increasingly reported in the literature; further studies should investigate the role of systematic screening and prophylaxis against infections in this subset of patients.

[Acute renal tubular damage caused by disseminated Trichosporon infection in primary myelofibrosis].

A 70-year-old man received a course of therapy that consisted of prednisolone, cyclosporine, and etoposide due to hemophagocytic syndrome which had developed during primary myelofibrosis. He also received micafungin (MCFG) as prophylaxis against a potential fungal infection. We diagnosed febrile neutropenia due to the hemophagocytic syndrome therapy and candidemia because Candida species were detected in blood cultures. He received liposomal amphotericin B (L-AMB) for the candidemia but did not respond to this treatment. Oliguria was diagnosed and renal failure progressed rapidly. We suspected that his renal failure had been induced by the antibiotics. We thus changed the antibiotic regimen but he died of progressive renal failure. We performed renal necropsy and diagnosed acute interstitial tubular nephritis, due to a yeast-like fungus that generally invades the renal tubules. The yeast-like fungus was later identified as Trichosporon asahii, rather than candida, by blood cultures. An immunocompromised host receiving MCFG for acute progressive renal failure requires an appropriate antifungal drug considering the possibility of disseminated Trichosporon.

Brucellosis presenting as myelofibrosis: first case report.

We describe the case of a 29-year-old woman who presented with pancytopenia and myelofibrosis. Brucella melitensis was identified in her blood. The patient recovered completely with doxycycline and rifampin. A repeat bone marrow biopsy showed hypercellularity without myelofibrosis. Bone marrow findings in cases of pancytopenia due to brucellosis reveal normocellularity, hypercellularity, hemophagocytosis, or granuloma. To our knowledge this is the first report of brucellosis causing myelofibrosis. Brucellosis should be considered as a possible cause of myelofibrosis in endemic areas.

A novel mechanism of fluconazole resistance associated with fluconazole sequestration in Candida albicans isolates from a myelofibrosis patient.

A series of 10 strains of Candida albicans, from TIMM 3309 to TIMM 3318, were repeatedly isolated in one myelofibrosis-complicated patient with recurrent candidemia. The latter five isolates, from TIMM 3314 to TIMM 3318, became suddenly resistant to fluconazole during the 10 to 16 weeks after antimycotic therapy. We investigated the resistant mechanism of fluconazole using one susceptible isolate and two of the five resistant isolates in the series. The ergosterol synthesis by cell-free extracts from the two resistant isolates was less susceptible to fluconazole partly as a result of a decreased affinity of cytochrome P-450. Unexpectedly, these two resistant isolates showed higher levels of an intracellular accumulation of [H]fluconazole than the susceptible isolate and the control strain of C. albicans ATCC 10231. In the resistant isolate, TIMM 3318, most intracellular incorporated fluconazole was distributed in the 12,000 X g pellet (P-120) fraction by centrifugation unlike the two susceptible strains. An observation of the ultrastructure of TIMM 3318 showed the most notable alteration to be the characteristic appearance of numerous vesicular vacuoles (diameter, 150 to 400 nm); these vacuoles were not observed, however, in either of the susceptible strains. A direct observation of the subcellular fraction prepared from TIMM 3318 by the electron microscopy negative-staining method suggests that most of the vesicular vacuoles were recovered in the P-120 fraction. These results suggest that fluconazole sequestration caused by vesicular vacuoles of the resistant isolate might act as a novel mechanism of fluconazole resistance besides the decreased affinity of cytochrome P-450.

Pneumocystis carinii pneumonia in patients with malignant haematological diseases: 10 years' experience of infection in GIMEMA centres.

A retrospective survey was conducted over a 10-year period (1990-99) among 52 haematology divisions in order to evaluate the clinical and laboratory characteristics and outcome of patients with proven Pneumocystis carinii pneumonia (PCP) complicating haematological diseases. The study included 55 patients (18 with non-Hodgkin's lymphoma, 10 with acute lymphoblastic leukaemia, eight with acute myeloid leukaemia, five with chronic myeloid leukaemia, four with chronic lymphocytic leukaemia, four with multiple myeloma, three with myelodysplastic syndrome, two with myelofibrosis and one with thalassemia) who developed PCP. Among these, 18 (33%) underwent stem cell transplantation; only two received an oral prophylaxis with trimethroprim/sulphamethoxazole. Twelve patients (22%) developed PCP despite protective isolation in a laminar airflow room. The most frequent symptoms were: fever (86%), dyspnoea (78%), non-productive cough (71%), thoracic pain (14%) and chills (5%); a severe hypoxaemia was present in 39 patients (71%). Chest radiography or computerized tomography showed interstitial infiltrates in 34 patients (62%), alveolar infiltrates in 12 patients (22%), and alveolar-interstitial infiltrates in nine patients (16%). Bronchoalveolar lavage was diagnostic in 47/48 patients, induced sputum in 9/18 patients and lung biopsy in 3/8 patients. The diagnosis was made in two patients at autopsy. All patients except one started a specific treatment (52 patients trimethroprim/sulphamethoxazole, one pentamidine and one dapsone). Sixteen patients (29%) died of PCP within 30 d of diagnosis. Multivariate analysis showed that prolonged steroid treatment (P < 0.006) and a radiological picture of diffuse lung involvement (P < 0.003) were negative diagnostic factors.

Parvovirus B19 induced red cell aplasia in myelofibrosis.

A 38-year-old female presented with moderate anaemia and a leucoerythroblastic blood film. Subsequent investigation showed myelofibrosis in cellular phase. Her haemoglobin quickly and spontaneously recovered with concurrent serological evidence of recent parvovirus B19 infection. This is the first report in the literature of parvovirus causing red cell aplasia in myelofibrosis.

Evidence for retrovirus in miniature swine with radiation-induced leukemia or metaplasia.

Biochemical and morphological evidence indicates that a type-C retrovirus is present in the blood of swine (both leukemic and nonleukemic) exposed to strontium-90 radiation. Nonexposed swine that were leukemic also had virus present. The virus was shown to contain an RNase-sensitive DNA polymerase activity with cation, detergent and template requirements similar to those of known viral reverse transcriptases. The buoyant density of the virus was 1.14 to 1.16 g/ml, which can be converted, by treatment with ether, to a virion core having a density of 1.20 to 1.23 g/ml. Linear regression analysis indicated a correlation between virus-associated DNA polymerase activity and the number of blast cells in the peripheral blood.

IgG-subclass-specific CMV reactivity in bone marrow transplant recipients.

IgG subclasses of cytomegalovirus (CMV) antiviral antibodies were determined in 37 donor-recipient pairs of bone marrow transplants (BMT). Bone marrow transplant recipients, like healthy persons, have a restricted immune reactivity, producing mainly two types of anti-CMV IgG: IgG1 and IgG3. Passively transfused specific antibody subclasses were readily measurable. Take of the transplant could be detected from the production of subclass IgG antiviral antibody 1-3 months after BMT of seronegative recipients with marrow from seropositive donors. Patients with protracted CMV infections or other severe diseases initially also produced CMV IgG1 and IgG3, but anti-CMV subclass titers then decreased. In severe disease, CMV was isolated from blood cells as well as from urine. In moderate infections, in which the patients recovered, CMV was isolated from urine but usually not from blood, and a strong and durable antiviral subclass response was measured.

Electron microscopical and biochemical investigations on retra viruses in spleen tissue in malignancy.

Simultaneous biochemical and electron microscopical investigations on surgically removed spleens yielded evidence for the presence of reverse transcriptase containing (Retra) virus in two patients with hematological malignancies with spleen involvement. In three other patients with hematological diseases and in one control patient, the spleens were negative in both assays. The results of these combined studies support the view, that retraviruses are present in human malignancies.