Vegan-vegetarian low-protein supplemented diets in pregnant CKD patients: fifteen years of experience

Regression equation for predicting dietary phosphorus intake based on estimated dietary protein intake: A multicenter cross-sectional study in China

BACKGROUND

Protein and phosphorus intake, which affect chronic kidney disease (CKD), is assessed using cumbersome food diaries. Therefore, more straightforward and accurate methods of assessing protein and phosphorus intake are needed. We decided to investigate the nutrition status and dietary protein and phosphorus intake of patients with stages 3, 4, 5, or 5D CKD.

METHODS

This cross-sectional survey included outpatients with CKD at seven class A tertiary hospitals in Beijing, Shanghai, Sichuan, Shandong, Liaoning, and Guangdong in China. Protein and phosphorus intake levels were calculated using 3-day food records. Protein levels and calcium and phosphorus serum concentrations were measured; urinary urea nitrogen was determined using a 24-h urine test. Protein and phosphorus intakes were calculated using the Maroni and Boaz formulas, respectively. The calculated values were compared with the recorded dietary intakes. An equation that regressed phosphorus intake on protein intake was constructed.

RESULTS

The average recorded energy and protein intake was 1637.5 ± 595.74 kcal/day and 56.97 ± 25.25 g/day, respectively. Overall, 68.8% of patients had a good nutrition status (grade A on the Subjective Global Assessment). The correlation coefficient between protein intake and calculated intake was 0.145 (P = 0.376) and that between phosphorus intake and calculated intake was 0.713 (P < 0.001).

CONCLUSION

Protein and phosphorus intakes correlated linearly. Chinese patients with stage 3-5 CKD had low daily energy intake but high protein intake. Malnutrition was present in 31.2% of patients with CKD. The phosphorus intake could be estimated from the protein intake.

The Role of Plant-Based Diets in Preventing and Mitigating Chronic Kidney Disease: More Light than Shadows

Chronic kidney disease (CKD) is a non-communicable disease that affects >10% of the general population worldwide; the number of patients affected by CKD is increasing due in part to the rise in risk factors such as obesity, hypertension, and diabetes mellitus. As many studies show, diet can be an important tool for preventing and mitigating the onset of non-communicable diseases. Plant-based diets (PBDs) are those that emphasize the consumption of plant foods and may or may not include small or moderate amounts of animal foods. Recently, these diets have received increasing interest because they have been associated with favourable effects on health and also appear to protect against the development and progression of CKD. PBDs, which are associated with protein restrictions, seem to offer adjunctive advantages in patients with chronic kidney disease, as compared to conventional low-protein diets that include animal proteins. The principal aims of this review are to provide a comprehensive overview of the existing literature regarding the role of plant-based diets and low-protein, plant-based diets in the context of chronic kidney disease. Moreover, we try to clarify the definition of plant-based diets, and then we analyse possible concerns about the use of PBDs in patients with chronic kidney disease (nutritional deficiency and hyperkalaemia risk). Finally, we offer some strategies to increase the nutritional value of plant-based low-protein diets. In the Materials and Methods section, many studies about plant-based diets and low-protein plant-based diets (e.g., the very-low-protein diet and vegan low-protein diet, LPD) in chronic kidney disease were considered. In the Results and Conclusion section, current data, most from observational studies, agree upon the protective effect of plant-based diets on kidney function. Moreover, in patients with advanced CKD, low-protein plant-based options, especially a very-low-protein diet supplemented with heteroanalogues (VLPDs), compared to a conventional LPD appear to offer adjunctive advances in terms of delaying dialysis and mitigating metabolic disturbances. However, further studies are necessary to better investigate the possible metabolic and cardiovascular advantages of plant-based LPDs versus conventional LPDs.

Personalized Low-Protein Diet Prescription in CKD Population: Merging Evidence From Randomized Trials With Observational Data

Nutritional therapy is a cornerstone of the clinical management of chronic kidney disease (CKD). Nevertheless, randomized controlled trials often have failed to show a relevant benefit of low-protein diets in nonselected CKD populations in terms of slowing the progression of kidney disease and need for dialysis. The more the target population is selected, the less the results can be generalizable to implement in clinical practice. On the contrary, observational studies, especially if performed with patient-centered, flexible approaches, point toward an extensive implementation of dietary protein restriction in different and unselected CKD populations. The observational evidence cannot be disregarded anymore. The most recent guidelines advise implementing low-protein diets or even very-low-protein diets in all CKD patients as early as stage 3. However, the lack of data from large randomized controlled trials on unselected CKD populations as well as on specific subpopulations, such as diabetic or obese patients, which nowadays comprise the majority of CKD subjects, reduces the generalizability of the recommendations. For some patient populations, such as those encompassing very old, nephrotic, or pregnant patients, the literature is even more limited because of the lower prevalence of these conditions and diffused prejudices against reducing protein intake. This pragmatic review discusses the need for integrating information derived from randomized trials with evidence derived from observational studies to guide feasible strategies for more successful implementation of low-protein diets in the treatment of all segments of the CKD population.

Glomerular diseases in pregnancy: pragmatic recommendations for clinical management

Our understanding of the various aspects of pregnancy in women with kidney diseases has significantly improved in the last decades. Nevertheless, little is known about specific kidney diseases. Glomerular diseases are not only a frequent cause of chronic kidney disease in young women, but combine many challenges in pregnancy: immunologic diseases, hypertension, proteinuria, and kidney tissue damage. An international working group undertook the review of available current literature and elicited expert opinions on glomerular diseases in pregnancy with the aim to provide pragmatic information for nephrologists according to the present state-of-the-art knowledge. This work also highlights areas of clinical uncertainty and emphasizes the need for further collaborative studies to improve maternal and fetal health.

Plant-Based Diets Improve Maternal-Fetal Outcomes in CKD Pregnancies

Reducing protein intake in patients with chronic kidney disease (CKD) limits glomerular stress induced by hyperfiltration and can prevent the progression of kidney disease; data in pregnancy are limited. The aim of this study is to analyze the results obtained in CKD patients who followed a plant-based moderately protein-restricted diet during pregnancy in comparison with a propensity-score-matched cohort of CKD pregnancies on unrestricted diets. A total of 52 CKD pregnancies followed up with a protein-restricted plant-based diet (Torino, Italy) were matched with a propensity score based on kidney function and proteinuria with CKD pregnancies with unrestricted protein intake (Cagliari Italy). Outcomes included preterm (<37 weeks) and very preterm (<34 weeks) delivery and giving birth to a small-for-gestational-age baby. The median age in our cohort was 34 years, 63.46% of women were primiparous, and the median body mass index (BMI) was 23.15 kg/m² with 13.46% of obese subjects. No statistical differences were found between women on a plant-based diet and women who were not in terms of age, parity, BMI, obesity, CKD stage, timing of referral, or cause of CKD. No differences were found between the two groups regarding the week of delivery. However, the combined negative outcome (birth before 37 completed gestational weeks or birth-weight centile <10) occurred less frequently in women following the diet than in women in the control group (61.54% versus 80.77%; p = 0.03). The lower risk was confirmed in a multivariable analysis adjusted for renal function and proteinuria (OR: 0.260 [Q1:0.093-Q3:0.724]; p = 0.010), in which the increase in proteinuria from the first to the last check-up before delivery was lower in patients on plant-based diets (median from 0.80 to 1.87 g/24 h; p: ns) than in controls (0.63 to 2.39 g/24 h p <0.0001). Plant-based, moderately protein-restricted diets in pregnancy in patients with CKD are associated with a lower risk of preterm delivery and small-for-gestational-age babies; the effect may be mediated by better stabilization of proteinuria.

Complex Management of Nephrotic Syndrome and Kidney Failure during Pregnancy in a Type 1 Diabetes Patient: A Challenging Case

Pregnancy with chronic kidney disease is challenging, and patients with diabetic nephropathy are at particular risk of a rapid kidney function decline during pregnancy. While indications for the management of pregnant patients with initial diabetic nephropathy are widely available in the literature, data on patients with severe nephrotic syndrome and kidney function impairment are lacking, and the decision on whether and when dialysis should be initiated is not univocal. We report a type 1 diabetes patient who started pregnancy with a severe nephrotic syndrome and shifted from CKD stage 3b to stage 5 during pregnancy. The management was complicated by a fetal heart malformation and by poorly controlled diabetes. The evidence for and against starting dialysis was carefully evaluated, and the choice of strict nephrological and obstetrical monitoring, nutritional management, and diuretic treatment made it possible to avoid dialysis in pregnancy, after ruling out pre-eclampsia. This experience enables examination of some open issues and contributes to the discussion of when to start dialysis in pregnancy.

Dialysis and a plant-based diet to achieve physiologic urea levels for fetal benefit: Normal pregnancy outcome despite chronic kidney disease and hypertension

Chronic kidney disease significantly increases the risk of adverse maternal and perinatal outcomes. A growing body of evidence suggests that intensive dialysis, achieving physiologic pre-dialysis blood urea, is associated with decreased morbidity. We report a case of a successful pregnancy outcome in a 32-year-old nulliparous woman with stage 4 chronic kidney disease who dialysed from 11 to 31 weeks, gestation for fetal benefit and concurrently trialled a plant-based diet. We hypothesise that her dietary changes assisted with urea reduction, enabling her to become dialysis independent. Although we must recognise that such pregnancies remain high risk, as demonstrated both in this case and more recent literature, advances in complex obstetric care and dialysis protocols may now give women with chronic kidney disease a realistic hope of a successful pregnancy.

Vegetarian Diet Was Associated With a Lower Risk of Chronic Kidney Disease in Diabetic Patients

Introduction

Diabetes mellitus (DM) is a pathological hyperglycemic state related to the dysregulation of insulin. Chronic kidney disease (CKD) is a common chronic complication in diabetic patients. A vegetarian diet could be one of the preventive strategies for the occurrence of CKD in patients with diabetes mellitus. However, it is still unknown whether a vegetarian diet lowers the occurrence of CKD in DM patients.

Research Design and Methods

This retrospective study was conducted at Taipei Tzu Chi Hospital from 5 September 2005 to 31 December 2016. Subjects with an HbA1c level > 6.5% or previous history of diabetes mellitus elder than 40 years were grouped based on self-reported dietary habits (vegetarians, lacto-ovo vegetarians and omnivores) in the structured questionnaire. Structural equation modeling (SEM) was applied to estimate the direct and indirect effects of variables on the occurrence of chronic kidney disease.

Results

Among these 2,797 subjects, the participants were grouped into dietary habits as vegans (n = 207), lacto-ovo vegetarians (n = 941) and omnivores (n = 1,649). The incidence of overall CKD was higher in the omnivore group [36.6% vs 30.4% (vegans) and 28.5% (lacto-ovo vegetarian), p < 0.001]. In the SEM model, after adjusting for age and sex, the lacto-ovo vegetarian [OR: 0.68, 95% confidence interval (CI): 0.57–0.82] and vegan groups (OR 0.68, 95% CI: 0.49–0.94) were both associated with a lower risk of CKD occurrence than the omnivore group. The vegan diet and lacto-ovo diet lowered the risk related to a high BMI (OR: 0.45, p < 0.001, OR: 0.58, p < 0.001) and hyperuricemia (OR: 0.53, p < 0.001; OR: 0.55, p < 0.001) for the occurrence of CKD.

Conclusion

Vegetarian dietary habits were associated with a lower occurrence of CKD in DM patients.

Chronic Kidney Disease: Role of Diet for a Reduction in the Severity of the Disease

Chronic kidney disease affects ~37 million adults in the US, and it is often undiagnosed due to a lack of apparent symptoms in early stages. Chronic kidney disease (CKD) interferes with the body's physiological and biological mechanisms, such as fluid electrolyte and pH balance, blood pressure regulation, excretion of toxins and waste, vitamin D metabolism, and hormonal regulation. Many CKD patients are at risk of hyperkalemia, hyperphosphatemia, chronic metabolic acidosis, bone deterioration, blood pressure abnormalities, and edema. These risks may be minimized, and the disease's progression may be slowed through careful monitoring of protein, phosphorus, potassium, sodium, and calcium, relieving symptoms experienced by CKD patients. In this review, the current Kidney Disease Outcomes Quality Initiative (KDOQI) recommendations are highlighted, reflecting the 2020 update, including explanations for the pathophysiology behind the recommendations. The Dietary Approaches to Stop Hypertension, the Mediterranean diet, and the whole foods plant-based diet are currently being examined for their potential role in delaying CKD progression. Biological explanations for why the whole foods plant-based diet may benefit CKD patients compared to diets that include animal products are examined. Strong evidence continues to support the importance of diet meeting the daily requirement in the prevention and progression of kidney disease, and medical nutrition therapy with a registered dietitian is a critical aspect in medical intervention for CKD.

Quality or Quantity of Proteins in the Diet for CKD Patients: Does "Junk Food" Make a Difference? Lessons from a High-Risk Pregnancy

BACKGROUND

How to manage patients with severe kidney disease in pregnancy is still a matter of discussion, and deciding if and when to start dialysis is based on the specialist's experience and dialysis availability. The effect of toxic substances usually cleared by the kidney may be more severe and readily evident. The review, and related case, underlines the importance of considering the presence of additives in food in delicate conditions, such as CKD pregnancy. The Case: A 39-year-old indigenous woman from a low-resourced area in Mexico was referred to the obstetric nephrology at 25 gestational weeks because of serum creatinine at 3.6 mg/dL, hypertension on low-dose alpha-methyl-dopa, and nephrotic-range proteinuria. Kidney ultrasounds showed small poorly differentiated kidneys; foetal ultrasounds detected a female foetus, normal for gestational age. The patient's baseline protein intake, which was estimated at 1.2-1.3 g/kg/day, was mostly of animal-origin (>70%) poor-quality food ("junk food"). In the proposed diet, protein intake was only slightly reduced (1.0-1.2 g/kg/day), but the source of proteins was changed (only 30% of animal origin) with attention to food quality. A remarkable decrease in BUN was observed, in concomitance with adequate dietary follow-up, with rapid rise of BUN when the patient switched temporarily back to previous habits. A healthy female baby weighing 2,460 g (11th centile for gestational age) was delivered at 37 gestational weeks. Discussion and Literature Review: While data on patients with chronic kidney disease are scant, the long list of contaminants present in food, especially if of low quality, should lead us to reflect on their potential negative effect on kidney function and make us realize that eating healthy, unprocessed "organic" food should be encouraged, in delicate conditions such as pregnancy and breastfeeding and for young children, in particular when kidney function is failing. The case herein described gave us the opportunity to reflect on the importance of diet quality and on the potential risks linked to food additives, many of which, including phosphates and potassium, are not declared on food labels, while others, including dyes, antioxidants, thickeners, emulsifiers, and preservatives, are qualitatively, but not quantitatively, reported.

Medical Nutritional Therapy for Patients with Chronic Kidney Disease not on Dialysis: The Low Protein Diet as a Medication

The 2020 Kidney Disease Outcome Quality Initiative (KDOQI) Clinical Practice Guideline for Nutrition in chronic kidney disease (CKD) recommends protein restriction to patients affected by CKD in stages 3 to 5 (not on dialysis), provided that they are metabolically stable, with the goal to delay kidney failure (graded as evidence level 1A) and improve quality of life (graded as evidence level 2C). Despite these strong statements, low protein diets (LPDs) are not prescribed by many nephrologists worldwide. In this review, we challenge the view of protein restriction as an "option" in the management of patients with CKD, and defend it as a core element of care. We argue that LPDs need to be tailored and patient-centered to ensure adherence, efficacy, and safety. Nephrologists, aligned with renal dietitians, may approach the implementation of LPDs similarly to a drug prescription, considering its indications, contra-indications, mechanism of action, dosages, unwanted side effects, and special warnings. Following this framework, we discuss herein the benefits and potential harms of LPDs as a cornerstone in CKD management.

End-Stage Kidney Disease and Dialysis in Pregnancy

End-stage kidney disease is associated with low fertility, with rates of conception in women on dialysis estimated at 1/100th of the general population. However, live birth rates are increasing over time in women on hemodialysis, whereas they remain lower and static in women on peritoneal dialysis. Intensification of hemodialysis, targeting a serum blood urea nitrogen <35 mg/dL or 36 hours of dialysis per week in women with no residual kidney function, is associated with improved live birth rates and longer gestational age. Even in intensively dialyzed cohorts, rates of prematurity and need for neonatal intensive care are high, upwards of 50%. Although women on peritoneal dialysis in pregnancy do not appear to be at increased risk of delivering preterm compared with those on hemodialysis, their infants are more likely to be small for gestational age. As such, hemodialysis has emerged as the preferred dialysis modality in pregnancy. Provision of specialized nephrology, obstetric, and neonatal care is necessary to manage these complex pregnancies and family planning counseling should be offered to all women with end-stage kidney disease.

Healthy adult vegetarians have better renal function than matched omnivores: a cross-sectional study in China

Background

An appropriate diet is an important determinant of kidney health. However, the association between vegetarian diets and renal function is unclear. We aimed to study the association between vegetarian diets and renal function in healthy adults.

Methods

A total of 269 vegetarians and 269 sex- and age-matched nonvegetarian omnivores were enrolled in this cross-sectional study. Basic characteristics and daily dietary intakes were assessed by face-to-face interviews. Blood samples were collected, and renal function was assessed by measuring blood urea nitrogen (BUN), serum creatinine (SCr), uric acid (UA) and the estimated glomerular filtration rate (eGFR). Blood pressure, fasting blood glucose and blood lipid profiles were also assessed.

Results

The average age of the vegetarians was 35.4 ± 8.6 years, 82.2% of whom were female. We evaluated the association between vegetarian diets and renal function using multivariate analysis. Compared with omnivores, vegetarians had lower BUN [β = − 0.63, 95% confidence interval (CI): (− 0.88, − 0.38)], SCr [β = − 2.04, 95% CI:(− 4.10, 0.02)], and UA levels [β = − 15.15, 95% CI: (− 27.81, − 2.50)] and higher eGFRs [β = 4.04, 95% CI: (0.30, 7.78)] after adjusting for sex, age, body mass index (BMI), physical activity, alcohol consumption, smoking status, low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), systolic pressure and fasting blood glucose. Further analysis of food composition and renal function showed that dietary fiber intake was significantly negatively associated with BUN [β = − 0.02, 95% CI: (− 0.03, 0.00)], SCr [β = − 0.14, 95% CI: (− 0.25, 0.04)], and UA levels [β = − 0.72, 95% CI: (− 1.36, 0.07)] and positively associated with the eGFR [β = 0.20, 95% CI: (0.00, 0.40)].

Conclusions

Healthy adult vegetarians have better renal function than omnivores, and the higher dietary fiber intake associated with vegetarian diets may contribute to the protective effect on renal function.

Nutrition care for chronic kidney disease during pregnancy: an updated review

Cases of chronic kidney disease (CKD), including CKD in pregnant women, have increased globally in recent years. CKD during pregnancy is associated with a higher risk of adverse outcomes, including gestational hypertension, preeclampsia, intrauterine growth restriction, and preterm birth, among others. Nutrition plays a significant role in many metabolic and physiological changes during pregnancy. Women with CKD are at increased risk of nutrition deficiencies and metabolic issues than women without CKD. Currently, we lack evidence regarding metabolic and nutritional adaptations during pregnancy in women with CKD and how these adaptations relate to perinatal outcomes. In this review, dietary and supplementation recommendations for CKD in adults and pregnant women are summarized from current clinical guidelines. We present the main nutrition care practices that have been studied in CKD pregnancies. This review will be helpful to health professionals as a preliminary reference for nutrition assessment and therapy in pregnant women with CKD.

Of Mice and Men: The Effect of Maternal Protein Restriction on Offspring's Kidney Health. Are Studies on Rodents Applicable to Chronic Kidney Disease Patients? A Narrative Review

In the almost 30 years that have passed since the postulation of the "Developmental Origins of Health and Disease" theory, it has been clearly demonstrated that a mother's dietary habits during pregnancy have potential consequences for her offspring that go far beyond in utero development. Protein malnutrition during pregnancy, for instance, can cause severe alterations ranging from intrauterine growth retardation to organ damage and increased susceptibility to hypertension, diabetes mellitus, cardiovascular diseases and chronic kidney disease (CKD) later in life both in experimental animals and humans. Conversely, a balanced mild protein restriction in patients affected by CKD has been shown to mitigate the biochemical derangements associated with kidney disease and even slow its progression. The first reports on the management of pregnant CKD women with a moderately protein-restricted plant-based diet appeared in the literature a few years ago. Today, this approach is still being debated, as is the optimal source of protein during gestation in CKD. The aim of this report is to critically review the available literature on the topic, focusing on the similarities and differences between animal and clinical studies.

Ameliorating Chronic Kidney Disease Using a Whole Food Plant-Based Diet

Novel approaches to ameliorating chronic kidney disease (CKD) are warranted as most patients are undiagnosed until they begin displaying symptoms of kidney failure. There is increasing evidence that a whole food plant-based (WFPB) diet may offer benefits that slow the progression of CKD, decrease the incidence cardiovascular disease, decrease rates of diabetes and obesity, and reduce inflammation and cholesterol, which in turn can delay kidney failure and the initiation of dialysis. While animal-based protein ingestion promotes an acidic environment, inflammation and renal hyperfiltration, study authors report plant-based protein can be alkaline-producing and anti-inflammatory and can contain renoprotective properties. Although there may be benefits to adopting a WFPB diet, macronutrient and micronutrient content should be carefully considered and adjusted to avoid malnutrition in CKD patients. Further research needs to be done in order to establish the biological plausibility and feasibility of a WFPB in individuals with diagnosed CKD.

Nutritional Challenges in Pregnant Women with Renal Diseases: Relevance to Fetal Outcomes

Pregnancy in women affected by chronic kidney disease (CKD) has become more common in recent years, probably as a consequence of increased CKD prevalence and improvements in the care provided to these patients. Management of this condition requires careful attention since many clinical aspects have to be taken into consideration, including the reciprocal influence of the renal disease and pregnancy, the need for adjustment of the medical treatments and the high risk of maternal and obstetric complications. Nutrition assessment and management is a crucial step in this process, since nutritional status may affect both maternal and fetal health, with potential effects also on the future development of adult diseases in the offspring. Nevertheless, few data are available on the nutritional management of pregnant women with CKD and the main clinical indications are based on small case series or are extrapolated from the general recommendations for non-pregnant CKD patients. In this review, we discuss the main issues regarding the nutritional management of pregnant women with renal diseases, including CKD patients on conservative treatment, patients on dialysis and kidney transplant patients, focusing on their relevance on fetal outcomes and considering the peculiarities of this population and the approaches that could be implemented into clinical practice.

Nutritional Therapy Modulates Intestinal Microbiota and Reduces Serum Levels of Total and Free Indoxyl Sulfate and P-Cresyl Sulfate in Chronic Kidney Disease (Medika Study)

In chronic kidney disease (CKD), the gut-microbiota metabolites indoxyl sulfate (IS) and p-cresyl sulfate (PCS) progressively accumulate due to their high albumin-binding capacity, leading to clinical complications. In a prospective crossover controlled trial, 60 patients with CKD grades 3B–4 (GFR = 21.6 ± 13.2 mL/min) were randomly assigned to two dietary regimens: (i) 3 months of free diet (FD) (FD is the diet usually used by the patient before being enrolled in the Medika study), 6 months of very low protein diet (VLPD), 3 months of FD and 6 months of Mediterranean diet (MD); (ii) 3 months of FD, 6 months of MD, 3 months of FD, and 6 months of VLPD. VLPD reduced inflammatory Proteobacteria and increased Actinobacteria phyla. MD and VLPD increased some butyrate-forming species of Lachnospiraceae, Ruminococcaceae, Prevotellaceae, Bifidobacteriaceae, and decrease the pathobionts Enterobacteriaceae. The increased level of potential anti-inflammatory Blautia and Faecalibacterium, as well as butyrate-forming Coprococcus and Roseburia species in VLPD was positively associated with dietary intakes and it was negatively correlated with IS and PCS. Compared to FD and MD, VLPD showed a lower amount of some Lactobacillus, Akkermansia, Streptococcus, and Escherichia species. MD and VLPD reduced both the total and free serum IS (MD −36%, −40% and VLPD −69%, −73%, respectively) and PCS (MD −38%, −44% and VLPD −58%, −71%, respectively) compared to FD. VLPD reduced serum D-lactate compared to MD and FD. MD and, to a greater extent, VLPD are effective in the beneficial modulation of gut microbiota, reducing IS and PCS serum levels, and restoring intestinal permeability in CKD patients.

Successful management of twin pregnancy in a woman with advanced chronic kidney disease: A case report

RATIONALE

Twin pregnancy in women with chronic kidney disease (CKD) is very rare but poses a great risk to both mother and children. In developing countries like China, advanced CKD twin pregnancies are often terminated. Here, we report a successful case and reviewed related cases, hope to facilitate further study.

PATIENT CONCERNS

A 29-year-old woman with a twin pregnancy showed serum creatinine (Scr) 100 μmol/L (CKD2) at conception. During her 12th week, Scr reached 263 μmol/L (CKD4) with urine protein 3+ and hypertension.

DIAGNOSES

Due to her pregnancy, renal biopsy was not considered. Lab tests showed deterioration of renal function and ultrasound detections showed small kidney size.

INTERVENTIONS

The patient was given basic drug therapy to control her blood pressure and supplemental nutrition without hemodialysis.

OUTCOMES

The patient delivered 2 healthy babies weighting 0.9 and 0.7 kg by cesarean section at the 28th week, but has been under maintenance hemodialysis since then.

LESSONS

Despite low birth weight and preterm delivery, successful twin pregnancies in some patients with CKD could be realized under early multidisciplinary intervention, but this poses great risks for mothers and twins, especially for patients with advanced CKD and those on hemodialysis.

Dialysis or a Plant-Based Diet in Advanced CKD in Pregnancy? A Case Report and Critical Appraisal of the Literature

Pregnancy is increasingly reported in chronic kidney disease (CKD), reflecting higher awareness, improvements in materno-foetal care, and a more flexible attitude towards “allowing” pregnancy in the advanced stages of CKD. Success is not devoid of problems and an important grey area regards the indications for starting dialysis (by urea level, clinical picture, and residual glomerular filtration rate) and for dietary management. The present case may highlight the role of plant-based diets in dietary management in pregnant CKD women, aimed at retarding dialysis needs. The case. A 28-year-old woman, affected by glomerulocystic disease and unilateral renal agenesis, in stage-4 CKD, was referred at the 6th week of amenorrhea: she weighed 40 kg (BMI 16.3), was normotensive, had no sign of oedema, her serum creatinine was 2.73 mg/dL, blood urea nitrogen (BUN) 35 mg/dL, and proteinuria 200 mg/24 h. She had been on a moderately protein-restricted diet (about 0.8 g/kg/real body weight, 0.6 per ideal body weight) since childhood. Low-dose acetylsalicylate was added, and a first attempt to switch to a protein-restricted supplemented plant-based diet was made and soon stopped, as she did not tolerate ketoacid and aminoacid supplementation. At 22 weeks of pregnancy, creatinine was increased (3.17 mg/dL, BUN 42 mg/dL), dietary management was re-discussed and a plant-based non-supplemented diet was started. The diet was associated with a rapid decrease in serum urea and creatinine; this favourable effect was maintained up to the 33rd gestational week when a new rise in urea and creatinine was observed, together with signs of cholestasis. After induction, at 33 weeks + 6 days, she delivered a healthy female baby, adequate for gestational age (39th centile). Urea levels decreased after delivery, but increased again when the mother resumed her usual mixed-protein diet. At the child’s most recent follow-up visit (age 4 months), development was normal, with normal weight and height (50th–75th centile). In summary, the present case confirms that a moderate protein-restricted diet can be prescribed in pregnancies in advanced CKD without negatively influencing foetal growth, supporting the importance of choosing a plant-based protein source, and suggests focusing on the diet’s effects on microcirculation to explain these favourable results.

Pregnancy in Chronic Kidney Disease: Need for Higher Awareness. A Pragmatic Review Focused on What Could Be Improved in the Different CKD Stages and Phases

Pregnancy is possible in all phases of chronic kidney disease (CKD), but its management may be difficult and the outcomes are not the same as in the overall population. The prevalence of CKD in pregnancy is estimated at about 3%, as high as that of pre-eclampsia (PE), a better-acknowledged risk for adverse pregnancy outcomes. When CKD is known, pregnancy should be considered as high risk and followed accordingly; furthermore, since CKD is often asymptomatic, pregnant women should be screened for the presence of CKD, allowing better management of pregnancy, and timely treatment after pregnancy. The differential diagnosis between CKD and PE is sometimes difficult, but making it may be important for pregnancy management. Pregnancy is possible, even if at high risk for complications, including preterm delivery and intrauterine growth restriction, superimposed PE, and pregnancy-induced hypertension. Results in all phases are strictly dependent upon the socio-sanitary system and the availability of renal and obstetric care and, especially for preterm children, of intensive care units. Women on dialysis should be aware of the possibility of conceiving and having a successful pregnancy, and intensive dialysis (up to daily, long-hours dialysis) is the clinical choice allowing the best results. Such a choice may, however, need adaptation where access to dialysis is limited or distances are prohibitive. After kidney transplantation, pregnancies should be followed up with great attention, to minimize the risks for mother, child, and for the graft. A research agenda supporting international comparisons is highly needed to ameliorate or provide knowledge on specific kidney diseases and to develop context-adapted treatment strategies to improve pregnancy outcomes in CKD women.

Pregnancy in a woman with recurrent immunoglobulin a nephropathy: A case report

Immunoglobulin A nephropathy (IgAN) is the most common form of primary glomerulonephritis and is increasingly encountered in pregnancy. The obstetric and renal outcomes of pregnancy are controversial, however. Women with IgAN are at higher risk of hypertension, preeclampsia and foetal loss; the prognosis is worse for those who have advanced chronic kidney disease and proteinuria. Here we report the case of a 32-year-old nulliparous woman with chronic hypertension who conceived during an active phase of her IgAN, which had been diagnosed 8 years earlier. Antihypertensive therapies and a low-protein diet were key to her reaching 34 weeks' gestation with acceptable kidney function. Rupture of membranes occurred at 34 weeks 3 days' gestation and a healthy boy was delivered the next day. This report aims to provide clinicians with useful information for the management of patients with IgAN during pregnancy.

The pregnancy outcomes in patients with stage 3-4 chronic kidney disease and the effects of pregnancy in the long-term kidney function

Objective

To investigate the pregnancy outcomes for patients with stage 3–4 chronic kidney disease (CKD) and the effects of pregnancy on kidney function.

Methods

Clinical data of pregnant women with CKD in the Peking University First Hospital between January 1st 2005 and October 1st 2016 were retrospectively analysed. The pregnancy outcomes of patients with different stages of CKD were compared. Patients with stage 3–4 CKD were followed up by telephone interview, and non-pregnant patients with stage 3–4 CKD were selected using the propensity score method to analyse the effects of pregnancy on kidney function.

Results

A total of 293 women with 300 pregnancies met the study criteria. There were 30 cases of stage 3–4 CKD. The incidence of adverse pregnancy outcomes of patients with stage 3–4 CKD was significantly higher than that with stage 1 CKD. The mean postpartum follow-up time of pregnant patients with CKD was 49.0 ± 33.1 months. A total of 26 cases of stage 3–4 CKD were followed up. During the follow-up period, 8 patients progressed to ESRD. A total of 28 non-pregnant patients with stage 3–4 CKD were selected as the control group. The results of multivariate analysis revealed that pregnancy did not increase the risk of deterioration of kidney function.

Conclusion

Patients with stage 3–4 CKD in early pregnancy had a significantly increased risk of adverse pregnancy outcomes. Pregnancy itself did not seem to accelerate kidney disease progression in patients with stage 3–4 CKD.

Nutritional treatment of advanced CKD: twenty consensus statements

The Italian nephrology has a long tradition and experience in the field of dietetic-nutritional therapy (DNT), which is an important component in the conservative management of the patient suffering from a chronic kidney disease, which precedes and integrates the pharmacological therapies. The objectives of DNT include the maintenance of an optimal nutritional status, the prevention and/or correction of signs, symptoms and complications of chronic renal failure and, possibly, the delay in starting of dialysis. The DNT includes modulation of protein intake, adequacy of caloric intake, control of sodium and potassium intake, and reduction of phosphorus intake. For all dietary-nutritional therapies, and in particular those aimed at the patient with chronic renal failure, the problem of patient adherence to the dietetic-nutritional scheme is a key element for the success and safety of the DNT and it can be favored by an interdisciplinary and multi-professional approach of information, education, dietary prescription and follow-up. This consensus document, which defines twenty essential points of the nutritional approach to patients with advanced chronic renal failure, has been written, discussed and shared by the Italian nephrologists together with representatives of dietitians (ANDID) and patients (ANED).

Successful pregnancy in a CKD patient on a low-protein, supplemented diet: an opportunity to reflect on CKD and pregnancy in Mexico, an emerging country

Pregnancy is probably the most important challenge in young women with chronic kidney disease (CKD). The challenge is greater in developing countries, in which access to dialysis is uneven, and prenatal care for CKD patients is not uniformly available. This case report summarizes some of the challenges faced by pregnant CKD women in a developing country. A 35-year-old woman, affected by an undiagnosed kidney disease, experienced preeclampsia at 24 years of age, and started dialysis in emergency at age 31 in the context of severe preeclampsia in her second pregnancy. Following slow recovery of kidney function, after 18 months of dialysis she started a moderately restricted, supplemented, low-protein diet, which allowed her to discontinue dialysis. A few months after dialysis discontinuation, she started a new pregnancy in the presence of severely reduced kidney function (serum creatinine 4.6 mg/dl at the last pre-pregnancy control). Interestingly, she discontinued nephrology and nutritional follow-up, mainly because she was worried that she would be discouraged from continuing the pregnancy, but also because she continued to feel well. She self-managed her diet in pregnancy and delivered a healthy baby, with normal intrauterine growth, at term; while the last laboratory data confirmed the presence of severe kidney function impairment, she is still dialysis-free at the time of the present report. Her story, with its happy ending, underlines the importance of dedicated programs for CKD pregnancies in developing countries and confirms the safety of moderately protein-restricted diets in pregnancy.

Pregnancy, Proteinuria, Plant-Based Supplemented Diets and Focal Segmental Glomerulosclerosis: A Report on Three Cases and Critical Appraisal of the Literature

Chronic kidney disease (CKD) is increasingly recognized in pregnant patients. Three characteristics are associated with a risk of preterm delivery or small for gestational age babies; kidney function reduction, hypertension, and proteinuria. In pregnancy, the anti-proteinuric agents (ACE-angiotensin converting enzyme-inhibitors or ARBS -angiotensin receptor blockers) have to be discontinued for their potential teratogenicity, and there is no validated approach to control proteinuria. Furthermore, proteinuria usually increases as an effect of therapeutic changes and pregnancy-induced hyperfiltration. Based on a favourable effect of low-protein diets on proteinuria and advanced CKD, our group developed a moderately protein-restricted vegan-vegetarian diet tsupplemented with ketoacids and aminoacids for pregnant patients. This report describes the results obtained in three pregnant patients with normal renal function, nephrotic or sub-nephrotic proteinuria, and biopsy proven diagnosis of focal segmental glomerulosclerosis, a renal lesion in which hyperfiltration is considered of pivotal importance (case 1: GFR (glomerular filtration rate): 103 mL/min; proteinuria 2.1 g/day; albumin 3.2 g/dL; case 2: GFR 86 mL/min, proteinuria 3.03 g/day, albumin 3.4 g/dL; case 3: GFR 142 mL/min, proteinuria 6.3 g/day, albumin 3.23 g/dL). The moderately restricted diet allowed a stabilisation of proteinuria in two cases and a decrease in one. No significant changes in serum creatinine and serum albumin were observed. The three babies were born at term (38 weeks + 3 days, female, weight 3180 g-62th centile; 38 weeks + 2 days, female, weight 3300 g-75th centile; male, 38 weeks + 1 day; 2770 g-8th centile), thus reassuring us of the safety of the diet. In summary, based on these three cases studies and a review of the literature, we suggest that a moderately protein-restricted, supplemented, plant-based diet might contribute to controlling proteinuria in pregnant CKD women with focal segmental glomerulosclerosis. However further studies are warranted to confirm the potential value of such a treatment strategy.

Vegetarian Diet in Chronic Kidney Disease-A Friend or Foe

Healthy diet is highly important, especially in patients with chronic kidney disease (CKD). Proper nutrition provides the energy to perform everyday activities, prevents infection, builds muscle, and helps to prevent kidney disease from getting worse. However, what does a proper diet mean for a CKD patient? Nutrition requirements differ depending on the level of kidney function and the presence of co-morbid conditions, including hypertension, diabetes, and cardiovascular disease. The diet of CKD patients should help to slow the rate of progression of kidney failure, reduce uremic toxicity, decrease proteinuria, maintain good nutritional status, and lower the risk of kidney disease-related secondary complications (cardiovascular disease, bone disease, and hypertension). It has been suggested that plant proteins may exert beneficial effects on blood pressure, proteinuria, and glomerular filtration rate, as well as results in milder renal tissue damage when compared to animal proteins. The National Kidney Foundation recommends vegetarianism, or part-time vegetarian diet as being beneficial to CKD patients. Their recommendations are supported by the results of studies demonstrating that a plant-based diet may hamper the development or progression of some complications of chronic kidney disease, such as heart disease, protein loss in urine, and the progression of kidney damage. However, there are sparse reports suggesting that a vegan diet is not appropriate for CKD patients and those undergoing dialysis due to the difficulty in consuming enough protein and in maintaining proper potassium and phosphorus levels. Therefore, this review will focus on the problem as to whether vegetarian diet and its modifications are suitable for chronic kidney disease patients.

'Let food be thy medicine…': lessons from low-protein diets from around the world

In this editorial we present the special issue dedicated to low-protein diets (LPDs) in chronic kidney disease, from a global perspective.The experiences gathered from several countries across all continents have created an issue which we hope you will find insightful, and lead to further discussion on this interesting topic.We discover that LPDs are feasible in both developed and low income countries, in patients where literacy is an issue, and are also safe, including during pregnancy and in old age.Patients prescribed a low protein diet are more inclined to follow and adhere to this change in lifestyle, provided the diet has been adapted to meet their own individual needs. With an increasing list of different menu options and better medical advice being offered we no longer need to identify low protein diets with a specific menu, ingredient or supplement, or with a specific level of protein restriction. Evidence shows how the best diet is often the one chosen by the patients, which doesn't drastically affect their day-to-day life, and delays the start of dialysis for as long as is safe under careful clinical control. The colourful menus gathered from all over the world remind us that a low protein diet does not necessarily mean that the pleasure of preparing a delicious meal is lost. The final comment is therefore dedicated to our patients: low protein diets can be beautiful.