Recurrent episodes of night blindness in a patient with short bowel syndrome

Neurological complications in patients undergoing general surgery: A literature review

Surgical procedures are extremely burdensome for patients, as in addition to complications directly related to the intervention, they expose the patient to further complications resulting from the disturbance of key functions of homeostasis in the body's systems, particularly the circulatory, respiratory, and nervous systems. Furthermore, they may contribute to the exacerbation of symptoms of underlying chronic diseases. This paper focuses on the most common possible neurological complications that may occur after surgical procedures and includes topics such as stroke, chronic pain, neuropathy, and delirium. The risk factors for neurological deficits, their known or possible etiology, the most characteristic symptoms, and potential preventive actions are discussed. The paper analyzes articles from the PubMed, ResearchGate, and Scopus databases. A surge0on's knowledge of possible complications that may occur in the perioperative period enables early recognition and effective reduction of their negative impact on the patient's functioning and quality of life after surgery, contributing to better overall treatment outcomes.

Vitamin A deficiency and the retinal "double carrot" sign with optical coherence tomography

BACKGROUND

Spectral-domain optical coherence tomography (SD-OCT) and full-field electroretinography (ERG) allow retinal assessment with vitamin A deficiency (VAD). Using SD-OCT, this study aimed to characterize and follow a novel retinal abnormality in patients with VAD and intramuscular supplementation.

METHODS

Patients with VAD were retrospectively reviewed, including SD-OCT and electroretinography.

RESULTS

Three patients had VAD following bariatric or colon surgery and varying supplementation. All had nyctalopia, extinguished scotopic rod-specific function with ERG, and decreased serum vitamin A. None demonstrated surface abnormalities. All received intramuscular vitamin A with subjective resolution of symptoms. On SD-OCT, four of six eyes exhibited homogenous foveal hyperreflectivity anterior to retinal pigment epithelium-Bruch complex, reminiscent of a "double carrot", which improved following supplementation. ERG findings demonstrated improved scotopic rod-specific function in all cases; however, photopic function remained diminished in two cases.

CONCLUSIONS

Structural improvement of the proposed "double carrot" sign occurs soon after vitamin A supplementation. While scotopic function improves rapidly following supplementation, cone function recovers more slowly. Therefore, foveal changes such as the "double carrot" sign suggest that structural recovery of cones precedes functional recovery.

Dark Adaptation and Its Role in Age-Related Macular Degeneration

Dark adaptation (DA) refers to the slow recovery of visual sensitivity in darkness following exposure to intense or prolonged illumination, which bleaches a significant amount of the rhodopsin. This natural process also offers an opportunity to understand cellular function in the outer retina and evaluate for presence of disease. How our eyes adapt to darkness can be a key indicator of retinal health, which can be altered in the presence of certain diseases, such as age-related macular degeneration (AMD). A specific focus on clinical aspects of DA measurement and its significance to furthering our understanding of AMD has revealed essential findings underlying the pathobiology of the disease. The process of dark adaptation involves phototransduction taking place mainly between the photoreceptor outer segments and the retinal pigment epithelial (RPE) layer. DA occurs over a large range of luminance and is modulated by both cone and rod photoreceptors. In the photopic ranges, rods are saturated and cone cells adapt to the high luminance levels. However, under scotopic ranges, cones are unable to respond to the dim luminance and rods modulate the responses to lower levels of light as they can respond to even a single photon. Since the cone visual cycle is also based on the Muller cells, measuring the impairment in rod-based dark adaptation is thought to be particularly relevant to diseases such as AMD, which involves both photoreceptors and RPE. Dark adaptation parameters are metrics derived from curve-fitting dark adaptation sensitivities over time and can represent specific cellular function. Parameters such as the cone-rod break (CRB) and rod intercept time (RIT) are particularly sensitive to changes in the outer retina. There is some structural and functional continuum between normal aging and the AMD pathology. Many studies have shown an increase of the rod intercept time (RIT), i.e., delays in rod-mediated DA in AMD patients with increasing disease severity determined by increased drusen grade, pigment changes and the presence of subretinal drusenoid deposits (SDD) and association with certain morphological features in the peripheral retina. Specifications of spatial testing location, repeatability of the testing, ease and availability of the testing device in clinical settings, and test duration in elderly population are also important. We provide a detailed overview in light of all these factors.

Vitamin A deficiency after prolonged intake of an unbalanced diet in a Japanese hemodialysis patient

BACKGROUND

In industrialized countries, vitamin A deficiency (VAD) is extremely rare, except association with bariatric surgeries and hepatobiliary disorders. It is unusual that VAD develops during hemodialysis due to reduced glomerular filtration of vitamin A-binding protein. We reported the case of a 58-year-old Japanese male hemodialysis patient diagnosed with VAD.

CASE PRESENTATION

The patient undergoing hemodialysis for more than 15 years presented with progressive photophobia and night blindness and was ophthalmologically examined. He denied a history of cancer or hepatobiliary disease and reported that he loved eating prepackaged noodle bowls and foods, with prolonged low intake of fruits/vegetables. He had good visual acuity. Fundus images showed numerous white dots in the midperipheral retinae, but no degenerative changes. In baseline full-field electroretinography (ERG), b-wave responses were extremely reduced in rod ERG, a-wave amplitudes in standard-flash/strong-flash ERG were reduced to 20-25% of our controls, a- and b-wave amplitudes in cone ERG were reduced to 40-50% of the controls. Whole-exome sequencing identified no pathogenic variant for any inherited retinal disorder. He was diagnosed with VAD because of reduced serum vitamin A levels and treated with retinol palmitate. Two months after treatment commencement, the serum vitamin A level was within the normal range. Full-field ERG showed that the scotopic ERG responses markedly improved compared with baseline.

CONCLUSIONS

This is the first report of VAD associated with undernutrition in the Japanese hemodialysis population.

Xerophthalmia: Findings from the Eye Lead to Diagnosis of a Fatal Intestinal Disease

Vitamin A has an essential role in the maintenance of corneal and conjunctival epithelization, as well as photoreceptor transduction in the retina. A deficiency of vitamin A causes keratinization of the surface epithelium, and night blindness is often the first symptom. This report describes a case of chronic intestinal pseudo-obstruction (CIPO), a rare and potentially fatal disease, diagnosed following detection of a vitamin A deficiency in an ophthalmological examination. A 25-year-old female patient presented with a 3-month history of dryness, a burning sensation, and decreased vision, especially at night, in both eyes. She appeared cachectic and ill, and reported having lost 10 kg in the previous year. An ophthalmological examination revealed conjunctival and corneal keratinization in addition to punctate keratopathy with xerosis in both eyes, which raised the suspicion of a vitamin A deficiency. Her serum vitamin A level confirmed the diagnosis, and she was referred to the gastroenterology clinic, where she was diagnosed with CIPO and treated with parenteral multivitamin supplementation. A vitamin A deficiency should be suspected in patients with malnourishment and xerosis. Rapid diagnosis and treatment can be life-saving in cases with a severe underlying pathology.

Microvascular Outcomes in Patients With Diabetes After Bariatric Surgery Versus Usual Care: A Matched Cohort Study

Background

Bariatric surgery improves glycemic control in patients with type 2 diabetes mellitus (T2DM), but less is known about microvascular outcomes.

Objective

To investigate the relationship between bariatric surgery and incident microvascular complications of T2DM.

Design

Retrospective matched cohort study from 2005 to 2011 with follow-up through September 2015.

Setting

4 integrated health systems in the United States.

Participants

Patients aged 19 to 79 years with T2DM who had bariatric surgery (n = 4024) were matched on age, sex, body mass index, hemoglobin A1c level, insulin use, diabetes duration, and intensity of health care use up to 3 nonsurgical participants (n = 11 059).

Intervention

Bariatric procedures (76% gastric bypass, 17% sleeve gastrectomy, and 7% adjustable gastric banding) compared with usual care.

Measurements

Adjusted Cox regression analysis investigated time to incident microvascular disease, defined as first occurrence of diabetic retinopathy, neuropathy, or nephropathy.

Results

Median follow-up was 4.3 years for both surgical and nonsurgical patients. Bariatric surgery was associated with significantly lower risk for incident microvascular disease at 5 years (16.9% for surgical vs. 34.7% for nonsurgical patients; adjusted hazard ratio [HR], 0.41 [95% CI, 0.34 to 0.48]). Bariatric surgery was associated with lower cumulative incidence at 5 years of diabetic neuropathy (7.2% for surgical vs. 21.4% for nonsurgical patients; HR, 0.37 [CI, 0.30 to 0.47]), nephropathy (4.9% for surgical vs. 10.0% for nonsurgical patients; HR, 0.41 [CI, 0.29 to 0.58]), and retinopathy (7.2% for surgical vs. 11.2% for nonsurgical patients; HR, 0.55 [CI, 0.42 to 0.73]).

Limitation

Electronic health record databases could misclassify microvascular disease status for some patients.

Conclusion

In this large, multicenter study of adults with T2DM, bariatric surgery was associated with lower overall incidence of microvascular disease (including lower risk for neuropathy, nephropathy, and retinopathy) than usual care.

Primary Funding Source

National Institute of Diabetes and Digestive and Kidney Diseases.

Serum carotenoids and macular pigment optical density in patients with intestinal resections and healthy subjects: an exploratory study

Reduced absorption capacity in patients with intestinal resections (IR) could result in malabsorption of fat-soluble components like carotenoids, which are of clinical interest in relation to visual health. In this case cohort, we investigated the association between IR and serum lutein, zeaxanthin, β-carotene and macular pigment optical density, when compared with healthy controls. Ten patients with IR and twelve healthy controls were included in the study. Baseline characteristics were comparable between groups, except for higher serum TAG (P < 0·05) and shorter bowel length (P < 0·0001) in the group with IR. Serum lutein, zeaxanthin, β-carotene and macular pigment optical density were >15 % lower in the patient group compared with healthy controls (P < 0·05, adjusted for age) and, in the case of serum lutein and zeaxanthin, also for dietary intake of carotenoids. Results suggest that for a test of macular carotenoid supplementation, subjects with a potentially clinically significant carotenoid deficit could be recruited among patients with IR.

Management and Complications of Short Bowel Syndrome: an Updated Review

Short bowel syndrome (SBS) is defined as loss of bowel mass from surgical resection, congenital defects, or disease. Intestinal failure (IF) includes the subset of SBS unable to meet nutrition needs with enteral supplements and requires parenteral nutrition (PN). The parenteral treatment of SBS is now a half-century old. Recent pharmacologic treatment (GLP-2 analogues) has begun to make a significant impact in the care and ultimate management of these patients such that the possibility of reducing PN requirements in formerly PN-dependent patients is a now a real possibility. Finally, newer understanding and possible treatment for some of the complications related to IF have more recently evolved and will be an emphasis of this report. This review will focus on developments over the last 10 years with the goal of updating the reader to new advances in our understanding of the care and feeding of the SBS patient.