Monitoring of serum magnesium levels during long-term use of proton pump inhibitors in elderly japanese patients: is it really necessary or not?

BACKGROUND: Long-term use of proton pump inhibitors (PPIs) has been found to significantly lower serum magnesium levels in patients in the USA and Europe. The package inserts of PPIs in these countries clearly state that healthcare professionals should consider monitoring magnesium levels prior to initiation of PPI treatment and periodically thereafter. However, the package inserts of PPIs in Japan do not clearly mention the monitoring of magnesium levels. In this study, we evaluated the relationship between long-term use of PPIs and the lower serum magnesium concentrations in elderly Japanese patients. METHODS: Using a retrospective observational approach, a total of 264 Japanese outpatients were included in the study. Patients over the age of 75 years were considered elderly. Serum magnesium levels of the patients were measured in units of 0.1 mg/dL between January 2016 and June 2022 at the Higo Internal Medicine Clinic and Ai Pharmacy in Kyoto, Japan. RESULTS: Four of the 264 eligible patients were diagnosed with hypomagnesemia. Three were PPI non-users, and one was a PPI user. Serum magnesium concentrations were significantly lower in PPI users (n = 47) than in non-users (n = 85; 2.1 ± 0.2 vs. 2.2 ± 0.3 mg/dL, p < 0.05) in the 132 elderly patients. Comorbidity included diabetes mellitus in both PPI users (23.4%) and non-users (57.6%) and hyperlipidemia in both PPI users (61.7%) and non-users (41.2%). CONCLUSION: PPIs are commonly used oral drugs for elderly patients. There was an association between the long-term use of PPIs and lower serum magnesium concentrations in elderly patients. Although the difference in the decrease in serum magnesium concentrations was within the normal range of serum magnesium levels, health care professionals should consider monitoring serum magnesium levels periodically in elderly patients receiving long-term PPIs.

Heterozygous Dnmt3a R878C induces expansion of quiescent hematopoietic stem cell pool.

Somatic mutation of DNMT3A (DNA methyltransferase 3 alpha) is implicated in the development of a wide range of hematological disorders, including clonal hematopoiesis of indeterminate potential. To elucidate the functional roles of endogenous levels of a DNMT3A R882 mutant, we generated a novel Dnmt3a R878C conditional knock-in mouse model. In contrast to viable heterozygotes, mice homozygous for the Dnmt3a R878C mutation in the hematopoietic system were not viable (Dnmt3a R878C is homologous to human DNMT3A R882C). Hematopoietic cell-specific heterozygous expression of Dnmt3a R878C led to significant expansion of adult quiescent hematopoietic stem cells (HSCs); however, these mice had no hematological malignancies. The expanding HSC population in heterozygous Dnmt3a R878C knock-in mice had an accumulation of G0-phase cells. In contrast to aberrantly enhanced self-renewal capacity in vitro, heterozygous Dnmt3a R878C knock-in HSCs had no competitive repopulating advantage in vivo over wild-type HSCs. Considering the capacity of the heterozygous Dnmt3a R878C mutant for HSC pool expansion, our Dnmt3a R878C knock-in mouse line is a useful platform on which to dissect the pathophysiology of clonal hematopoiesis. This mouse line can also help to elucidate the biological and molecular actions of DNMT3A mutations in the malignant transformation of normal HSCs.

[Osteonecrosis developing after rituximab-containing chemotherapy for Waldenström macroglobulinemia].

A 71-year-old woman presented with fever, weight loss, and anemia because of recurrent Waldenström macroglobulinemia (WM) with cryoglobulinemia. Treatment with five cycles of doxorubicin, vincristine, cyclophosphamide, and prednisolone (CHOP) therapy was initiated, which resulted in insufficient improvement in anemia. Hence, a combination of rituximab and CHOP therapy was subsequently initiated. The patient complained of lumbago and lower leg pain on day 4 of the chemoimmunotherapy. X-ray findings for the affected sites were unremarkable, and the patient's symptoms gradually and spontaneously subsided. Rituximab monotherapy was then administered, which resulted in the deterioration of her symptoms. Magnetic resonance imaging revealed osteonecrosis of the bilateral distal ends of the femur, and proximal and distal ends of the tibia. This is the first case of lower leg osteonecrosis complicating chemoimmunotherapy for WM. Osteonecrosis may be an unusual adverse effect of rituximab therapy for WM. Tumor lysis by rituximab may have contributed to the pathogenesis of this complication. MRI assessment should be considered when WM patients complain of bone pain following rituximab-containing chemotherapy.

Ovarian Seromucinous Borderline Tumor and Clear Cell Carcinoma: An Unusual Combination.

Ovarian seromucinous borderline tumors (SMBTs) are rare. They architecturally resemble serous borderline tumors but are much more frequently associated with endometriosis. The coexistence of other tumors with seromucinous tumors is also extremely rare. Here, we report an unusual combination of bilateral ovarian SMBT and clear cell carcinoma associated with polypoid endometriosis of the colon, in a 62-year-old woman. There was no transitional lesion between the two tumors. Immunohistochemistry showed different staining patterns in tumor components. Seromucinous tumor cells were positive for estrogen receptor (ER) and progesterone receptor (PgR) but negative for Napsin A, p504S, and HNF1B. Clear cell tumor cells were positive for Napsin A and p504S and focally positive for HNF1B but negative for ER and PgR. Loss of ARID1A expression was not observed in SMBTs, clear cell tumors, or endometriosis. These findings suggest that these tumors arose from separate endometriosis foci and collided within the same ovary. To the best of our knowledge, this is the first case of this unusual combination of ovarian seromucinous tumor and clear cell carcinoma to be reported in the English literature.

Cerebral embolism through hematogenous dissemination of pulmonary mucormycosis complicating relapsed leukemia.

Invasive mucormycosis in patients with hematological diseases mostly occurs in the lungs. Invasive mucormycosis of other anatomical sites is relatively infrequent and its pathogenesis has not so far been well elucidated. Here, we describe an autopsy case of pulmonary invasive mucormycosis complicated by cerebral embolism with infarct. A 77-year-old Japanese woman with relapsed acute myeloid leukemia complained of left visual disturbance and weakness of the lower limbs. The diagnosis of leukemic infiltration to the central nervous system was made. Repeated intrathecal injection of methotrexate plus cytarabine resulted in partial amelioration of the neurologic symptoms. However, the patient then developed fever, dyspnea, and subsequent right hemiparesis. A computed tomography (CT) scan showed a consolidative shadow with halo sign in the left lung field, which was compatible with either invasive pulmonary aspergillosis or mucormycosis. These findings accounted for fever and dyspnea, but not hemiparesis. Despite antifungal therapy, the patient succumbed to death after two weeks. Autopsy revealed pulmonary invasive mucormycosis with a fungal ball in the lumina of the adjacent ascending aorta. Intriguingly, autopsy and postmortem CT scan identified left cerebral infarct due to mucormycosis, which accounted for the right hemiparesis. It is likely that the fungal ball caused the cerebral embolism through hematogenous dissemination. We should suspect hematogenous dissemination when we see a patient with pulmonary invasive mucormycosis developing neurologic symptoms.

A frameshift mutation in the canine HEXB gene in toy poodles with GM2 gangliosidosis variant 0 (Sandhoff disease).

GM2 gangliosidosis variant 0 (Sandhoff disease, SD) is a fatal, progressive neurodegenerative lysosomal storage disease caused by mutations in the HEXB gene. Toy poodles recently were reported as the second breed of dog with SD. The present paper describes the molecular defect of this canine SD as the first identification of a pathogenic mutation in the canine HEXB gene. Genomic and complementary DNA sequences covering exonic regions of the canine HEXB gene, except exon 1, were analysed using DNA and RNA in an affected dog. A homozygous single base pair deletion of guanine in exon 3 was identified at nucleotide position 283 of the putative open reading frame (c.283delG). This mutation has the potential to cause a frameshift resulting in the alteration of valine at amino acid position 59 to a stop codon (p.V59fsX). Genotyping using the mutagenically separated PCR method demonstrated a correlation between phenotype and genotype in dogs with a pedigree related to the disease and that the mutation was rare in a randomly-selected population of toy poodles. These results strongly suggest that the deletion is pathogenic.

Dihydropyrimidinase deficiency: the first feline case of dihydropyrimidinuria with clinical and molecular findings.

Dihydropyrimidinase (DHP, EC 3.5.2.2) is the second enzyme of the pyrimidine degradation pathway and a deficiency of this enzyme is responsible for a rare inborn metabolic syndrome characterized by dihydropyrimidinuria. Here we report a cat with DHP deficiency, manifesting malnutrition, depression, vomiting, and hyperammonemia. A gas chromatographic-mass spectrometric analysis of urinary metabolic substances showed the presence of large amounts of dihydrouracil and dihydrothymine and moderate amounts of uracil and thymine, suggesting DHP deficiency. Analysis of the feline DPYS gene encoding DHP demonstrated that the cat was homozygous for the missense mutation c.1303G>A (p.G435R) in exon 8, which corresponds to a known mutation in a human patient with DHP deficiency. Population screening in 1,000 cats did not reveal any animal possessing this mutation, suggesting the prevalence of the mutant allele to be very low. This is the first report of naturally occurring DHP deficiency in animals and the cat represents a model of the human disease.

Rapid and simple polymerase chain reaction-based diagnostic assays for GM2 gangliosidosis variant 0 (Sandhoff-like disease) in Japanese domestic cats.

Polymerase chain reaction (PCR)-based assays combined with microchip electrophoresis were developed and evaluated for diagnosis and genotyping of GM2 gangliosidosis variant 0 (Sandhoff-like disease) in Japanese domestic cats. A preliminary genotyping survey was carried out in the population of Japanese domestic cats (1,015 cats in total) in southern Japan. Three kinds of assays including PCR primer-induced restriction analysis (PIRA) and mutagenically separated (MS)-PCR were carried out using blood-stained Flinders Technology Associates filter papers (FTA cards) as templates. The PCR products were analyzed by both agarose gel and microchip electrophoreses. All assays were sufficient to determine the genotypes of this disease, but MS-PCR offered the most rapid and simplest test, as it does not need the restriction enzyme step required in PCR-PIRA. The use of microchip electrophoresis in combination with FTA cards for sampling could shorten the time required for genotyping and simplify the procedure as well. The genotyping survey in the current study did not find any cats that possessed the mutant allele, suggesting that the prevalence of this allele is low (<0.1%) in southern Japan.

Monitoring minimization of grade B environments based on risk assessment using three-dimensional airflow measurements and computer simulation.

A practical, risk-based monitoring approach using the combined data collected from actual experiments and computer simulations was developed for the qualification of an EU GMP Annex 1 Grade B, ISO Class 7 area. This approach can locate and minimize the representative number of sampling points used for microbial contamination risk assessment. We conducted a case study on an aseptic clean room, newly constructed and specifically designed for the use of a restricted access barrier system (RABS). Hotspots were located using three-dimensional airflow analysis based on a previously published empirical measurement method, the three-dimensional airflow analysis. Local mean age of air (LMAA) values were calculated based on computer simulations. Comparable results were found using actual measurements and simulations, demonstrating the potential usefulness of such tools in estimating contamination risks based on the airflow characteristics of a clean room. Intensive microbial monitoring and particle monitoring at the Grade B environmental qualification stage, as well as three-dimensional airflow analysis, were also conducted to reveal contamination hotspots. We found representative hotspots were located at perforated panels covering the air exhausts where the major piston airflows collect in the Grade B room, as well as at any locations within the room that were identified as having stagnant air. However, we also found that the floor surface air around the exit airway of the RABS EU GMP Annex 1 Grade A, ISO Class 5 area was always remarkably clean, possibly due to the immediate sweep of the piston airflow, which prevents dispersed human microbes from falling in a Stokes-type manner on settling plates placed on the floor around the Grade A exit airway. In addition, this airflow is expected to be clean with a significantly low LMAA. Based on these observed results, we propose a simplified daily monitoring program to monitor microbial contamination in Grade B environments. To locate hotspots we propose using a combination of computer simulation, actual airflow measurements, and intensive environmental monitoring at the qualification stage. Thereafter, instead of particle or microbial air monitoring, we recommend the use of microbial surface monitoring at the main air exhaust. These measures would be sufficient to assure the efficiency of the monitoring program, as well as to minimize the number of surface sampling points used in environments surrounding a RABS.

Establishment of critical contamination risk locations ("hot spots") in environmental monitoring by means of three-dimensional airflow analysis and particulate evaluation.

A practical approach for the qualification of the surrounding environment of the critical area in aseptic processing has been developed. This method uses three-dimensional air velocity measurements combined with airborne particle monitoring. The analysis of the results obtained using the methods described in this article are beneficial in the selection of sample sites and frequencies and in refining personnel procedures and materials flow in aseptic processing. We propose that this improved qualification method can be widely applicable for both existing and new aseptic processing areas. This paper shows the results of one case study utilizing this method. The particle distribution map of a Grade B environment based upon extensive analysis was found to correspond to room airflow, as visualized by air vector mapping. The actual annual environmental monitoring data, which include airborne particles and microbes, as well as other microbial monitoring data, are also presented with respect to their relationship to the airflow pattern.