Light-Chain (AL) Cardiac Amyloidosis Presenting as Heart Failure With Reduced Ejection Fraction

Systemic amyloidosis is caused by the extracellular deposition of misfolded proteins in various organs and usually leads to organ dysfunction. The two common subtypes include light-chain amyloidosis and transthyretin amyloidosis. Deposition of these proteins in the heart can lead to infiltrative and restrictive cardiomyopathy, commonly manifesting as heart failure with preserved ejection fraction. However, systolic heart failure with reduced ejection fraction is mainly seen in the advanced stages of the disease. Here, we present the case of a 53-year-old female who presented with new-onset heart failure with reduced ejection fraction with no prior symptoms or diagnosis of amyloidosis and diastolic dysfunction.

Benign Pneumoperitoneum Following Mitral Valve Replacement

The pneumoperitoneum refers to the presence of free air inside the abdominal cavity. This finding is usually a sequela of a gastrointestinal tract perforation. Still, in rare instances, it can present after cardiac surgery due to the proximity of the peritoneal cavity and pericardium, allowing air to enter the peritoneal cavity. Our patient was a 63-year-old female who initially presented for revision of the mitral valve replacement. A chest X-ray on postoperative day 13 revealed a 6.6 cm lucency under the right diaphragm suggestive of pneumoperitoneum. She was discharged after serial chest X-rays revealed a decrease in the size of the pneumoperitoneum. Twelve days later, our patient was readmitted, as another chest X-ray revealed that the size of the pneumoperitoneum was again increasing. An endoscopy was performed, but it did not reveal any lesions or etiology that would lead to a leak from the gastrointestinal tract. Finally, due to the benign nature of the pneumoperitoneum and the decrease in its size over the following days, we opted for conservative management, and she was discharged again. This case emphasizes the rare occurrence of benign pneumoperitoneum post-mitral valve surgery. While surgery may not always be required for asymptomatic cases, careful vigilance post-cardiac surgery remains crucial to detect potential abdominal complications promptly.

A Rare Case of Candida glabrata Cervical Spondylodiscitis

Introduction

Invasive candidiasis can lead to numerous life-threatening sequelae. Candida glabrata is the second-most common causative species of invasive candidiasis. This species possesses a high risk for persistent infection and candidemia. An uncommon complication of invasive candidiasis is spondylodiscitis and can rarely affect the cervical spine.

Case Presentation

The patient is a female in her late 50s with a complex medical history inclusive of chronic obstructive pulmonary disease, chronic pain, multiple abdominal surgeries, prolonged intensive care unit admission, and administration of total parenteral nutrition and broad-spectrum antibiotics who presented with complaints of worsening neck pain. She was last hospitalized 3 months prior and found to have C glabrata fungemia but was nonadherent to antifungal therapy.She was found to have advanced C5-6 spondylodiscitis and an epidural abscess. Her surgical cultures grew C glabrata. Despite surgical intervention and antimicrobial therapy, she clinically deteriorated and acquired septic shock with multiorgan failure.

Conclusion

This is a rare case of cervical spondylodiscitis caused by a deep-seated C glabrata infection.

An Unusual Case of Nonbacterial Thrombotic Endocarditis Attributable to Malignancy

Nonbacterial thrombotic endocarditis (NBTE), also known as marantic endocarditis, is a condition characterized by the deposition of thrombi and fibrin on normal or degenerated cardiac valves in the absence of microorganisms. We report a case of a 60-year-old male with nonbacterial thrombotic endocarditis found on transesophageal echocardiogram (TEE) after a normal TEE just one month prior. Our patient presented with abdominal pain associated with poor appetite and unintentional 20-pound weight loss for one month. Chest computed tomography revealed the presence of a mass-like opacification in the right lung middle lobe with moderate pericardial effusions. A biopsy of the mass confirmed malignancy consistent with lung primary adenocarcinoma. Subsequently, during hospitalization, the patient developed left lower extremity pain. Arterial ultrasound showed occlusion of the distal left popliteal artery for which he underwent thrombectomy of the left superficial femoral artery, balloon angioplasty of the left posterior tibial artery, and left popliteal artery. Repeat TEE during current hospitalization revealed a large 2 cm vegetation on the noncoronary cusp of the aortic valve. Studies for infective endocarditis were unremarkable. Subsequently, he was treated with aortic valve replacement and anticoagulation. After discharge, he returned with bilateral occipital infarcts four days later and expired.

Ileocecal Mesentery Arteriovenous Malformation as a Rare Cause of Ectopic Variceal Bleeding in a 58-Year-Old Male With Cirrhosis

Ectopic varices can be defined as dilated portosystemic venous collaterals that are located at a site other than the esophagus or stomach. These varices can be seen in patients with underlying portal hypertension, but bleeding from them is quite rare. The bleeding usually occurs in patients with a history of intra-abdominal surgery and adhesions. These varices are commonly found in the duodenum or rectum, but they can be present anywhere along the gastrointestinal tract. Currently, there are no well-established guidelines regarding the diagnosis and management of these variceal bleeds, and further investigations with randomized controlled or large-scale trials are required. Here, we report an unusual case of ectopic variceal bleeding from an ileal arteriovenous malformation (AVM), which presented as syncope associated with an acute abdomen in a patient with no prior history of intra-abdominal surgery.

A Body Now, Perhaps Once Someone

Description Personally driven by compassion in hospital medicine, I can't help but pen down certain emotions we experience as caregivers. It feels too selfish to not share some of those emotions, as profound as they are, though we seldom are aware that such feelings exist, even as they become palpable during adverse outcomes. Most of the time, thankfully the sick patients we encounter, recover and are discharged home. There are smiles of relief and gratitude to our profession as healers. But at times, with certain incurable conditions, we only can treat and try our best as doctors. There are tears, broken hearts, feelings of dread towards an approaching, certain end that we bitterly fight against, but lose. Commiserating with a patient in pain and with their loved ones is natural as a physician. And in this work, I share one of those unfortunate moments.

Comparative clinical study of the efficacy and safety of a S-metoprolol ER tablet versus a racemate metoprolol ER tablet in patients with chronic stable angina

OBJECTIVE

To compare the efficacy and safety of a S-metoprolol extended release (ER) tablet (50 mg) versus a racemate metoprolol ER tablet (100 mg) in the management of angina.

METHODS

An open-label, prospective, comparative study in a clinical setting was conducted in Indian patients. Patients (n = 50 in each group) with a history of angina pectoris, with or without hypertension, were administered study medications in a sequential 1:1 manner once daily for 8 weeks. The primary efficacy variable was a mean change from baseline in the number of angina attacks. The secondary efficacy variables were: mean change from baseline in the proportion of patients with no angina attacks, systolic blood pressure, diastolic blood pressure, heart rate, and proportion of blood pressure responders. Number of patients reporting adverse effects (AEs) and severity of AEs in both of the groups were compared.

RESULTS

All patients (n = 100) completed the study. In the S-metoprolol group the number of angina attacks (mean +/- SEM) at baseline and after 2, 4 and 8 weeks of therapy were 6.3 +/- 0.8, 3 +/-0.4, 1.8 +/- 0.4 and 0.7 +/- 0.2, respectively. In the metoprolol group these values were 5.8 +/-1, 3 +/- 0.7, 1.4 +/- 0.3 and 0.7 +/- 0.2, respectively. The reduction in the number of angina attacks from baseline was significant (p < 0.0001) in both groups with no between-group difference. The response rate in angina (percentage of patients completely relieved of angina attacks clinically) was greater in the S-metoprolol group (72%) when compared to the metoprolol group (62%) (p > 0.05, NS). Both study groups showed significant (p < 0.0001) reduction in baseline systolic blood pressure (SBP), diastolic blood pressure (SBP) and heart rate (HR) in hypertensive patients and a clinically non-significant (p > 0.05, NS) change in normotensive patients. Among hypertensive patients, the response rate in angina was higher in the S-metoprolol group (74%) when compared to the metoprolol group (61%) (p > 0.05, NS). In the S-metoprolol group four patients reported AEs: fatigue (n = 4), dry mouth (n = 1), dizziness (n = 1), dyspnea (n = 2), and mild rash (n = 1). In the metoprolol group three patients reported AEs: fatigue (n = 2), dyspnea (n = 1) and dizziness (n = 1). No statistically significant difference was detected between the groups in AE frequency/severity.

CONCLUSION

In routine clinical practice in the management of angina (with or without coexisting hypertension), S-metoprolol administered at half the dose of the racemate, shows similar efficacy, safety and a trend towards a higher response rate.

Comparison of the symbiotic and competition phenotypes of Sinorhizobium meliloti PHB synthesis and degradation pathway mutants

The competitive abilities of Sinorhizobium meliloti mutant strains containing lesions in the PHB synthesis (phbC) and degradation (bdhA) pathways were compared. While the bdhA mutant showed no noticeable symbiotic defects on alfalfa host plants when inoculated alone, in mixed inoculation experiments it was found to be less competitive than the wild type for nodule occupancy. Long-term survival of the bdhA mutant on a carbon-limiting medium was not affected. However, when subjected to competition with the wild-type strain in periodic subculturing through alternating carbon-limiting and carbon-excess conditions, the bdhA mutant performed poorly. A more severe defect in competition for growth and nodule occupancy was observed with a mutant unable to synthesize PHB (phbC). These results indicate that the ability to efficiently deposit cellular PHB stores is a key factor influencing competitive survival under conditions of fluctuating nutrient carbon availability, whereas the ability to use these stores is less important.

Poly-3-hydroxybutyrate degradation in Rhizobium (Sinorhizobium) meliloti: isolation and characterization of a gene encoding 3-hydroxybutyrate dehydrogenase

We have cloned and sequenced the 3-hydroxybutyrate dehydrogenase-encoding gene (bdhA) from Rhizobium (Sinorhizobium) meliloti. The gene has an open reading frame of 777 bp that encodes a polypeptide of 258 amino acid residues (molecular weight 27,177, pI 6.07). The R. meliloti Bdh protein exhibits features common to members of the short-chain alcohol dehydrogenase superfamily. bdhA is the first gene transcribed in an operon that also includes xdhA, encoding xanthine oxidase/dehydrogenase. Transcriptional start site analysis by primer extension identified two transcription starts. S1, a minor start site, was located 46 to 47 nucleotides upstream of the predicted ATG start codon, while S2, the major start site, was mapped 148 nucleotides from the start codon. Analysis of the sequence immediately upstream of either S1 or S2 failed to reveal the presence of any known consensus promoter sequences. Although a sigma54 consensus sequence was identified in the region between S1 and S2, a corresponding transcript was not detected, and a rpoN mutant of R. meliloti was able to utilize 3-hydroxybutyrate as a sole carbon source. The R. meliloti bdhA gene is able to confer upon Escherichia coli the ability to utilize 3-hydroxybutyrate as a sole carbon source. An R. meliloti bdhA mutant accumulates poly-3-hydroxybutyrate to the same extent as the wild type and shows no symbiotic defects. Studies with a strain carrying a lacZ transcriptional fusion to bdhA demonstrated that gene expression is growth phase associated.

Methylmalonyl-CoA mutase encoding gene of Sinorhizobium meliloti

A cluster of genes on megaplasmid pRmeSU47b, bhbA-D, is required for growth on the polyhydroxyalkanoate degradation pathway intermediates 3-hydroxybutyrate and acetoacetate as sole carbon source. DNA sequence analysis of the bhbA gene indicated that it encoded a protein of 712 amino acids (aa) (78kDa) which appeared to be a homodimeric methylmalonyl-CoA mutase enzyme (EC 5.4.99.2). Cell-free extract of a bhbA::Tn5 mutant was devoid of methylmalonyl-CoA mutase activity, thus confirming the identity of the bhbA-encoded enzyme. The reason for the requirement of methylmalonyl-CoA mutase activity for operation of the polyhydroxyalkanoate degradation pathway is not immediately apparent. Situated immediately upstream of bhbA, in the same orientation, is a gene which is predicted to encode a protein that exhibits remarkable sequence similarity to the alpha subunit of propionyl-CoA carboxylase (EC 6.4.1.3). A mutation in this gene did not affect ability to grow on 3-hydroxybutyrate as sole carbon source. Downstream of, and oriented towards bhbA, was identified a member of the GNTR class of transcriptional regulator-encoding genes. It is not yet known whether this regulatory protein is directly involved in modulation of bhbA expression.

Megaplasmid and chromosomal loci for the PHB degradation pathway in Rhizobium (Sinorhizobium) meliloti

Chromosomal and megaplasmid loci that affect the poly-3-hydroxybutyrate (PHB) degradation pathway in Rhizobium meliloti were identified. A clone that restores the ability of certain R. meliloti mutants with defined deletions in megaplasmid pRmeSU47b to use 3-hydroxybutyrate or acetoacetate as the sole carbon source was isolated from a cosmid library of R. meliloti genomic DNA. Tn5 insertion mutagenesis, followed by merodiploid complementation analysis, demonstrated that the locus consists of at least four transcriptional units, bhbA-D. We also identified loci involved in 3-hydroxybutyrate and/or acetoacetate utilization by screening for mutants that had lost the ability to use 3-hydroxybutyrate as the sole carbon source while retaining the ability to use acetate (thus ensuring an intact glyoxylate cycle and gluconeogenic pathway). These mutants fell into four classes, as determined by replicon mobilization experiments and genetic linkage in phage transduction; one class corresponded to the bhb locus on pRmeSU47b, two classes mapped to different regions on the chromosome and the fourth, bdhA, represented by a single mutant, mapped to another pRmeSU47b locus, near bacA. The bdhA mutant is deficient in 3-hydroxybutrate dehydrogenase activity.