Related Articles

Background

Cyclic vomiting syndrome (CVS), defined by recurrent stereotypical episodes of nausea and vomiting, is a relatively-common disabling and historically difficult-to-treat condition associated with migraine headache and mitochondrial dysfunction. Limited data suggests that the anti-migraine therapies amitriptyline and cyproheptadine, and the mitochondrial-targeted cofactors co-enzyme Q10 and L-carnitine, have efficacy in episode prophylaxis.

Methods

A retrospective chart review of 42 patients seen by one clinician that met established CVS diagnostic criteria revealed 30 cases with available outcome data. Participants were treated on a loose protocol consisting of fasting avoidance, co-enzyme Q10 and L-carnitine, with the addition of amitriptyline (or cyproheptadine in those < 5 years) in refractory cases. Blood level monitoring of the therapeutic agents featured prominently in management.

Results

Vomiting episodes resolved in 23 cases, and improved by > 75% and > 50% in three and one additional case respectively. Among the three treatment failures, two could not tolerate amitriptyline (as was also the case in the child with only > 50% efficacy) and one had multiple congenital gastrointestinal anomalies. Excluding the latter case, substantial efficacy (> 75% response) was 26/29 at the start of treatment, and 26/26 in those able to tolerate the regiment, including high dosages of amitriptyline.

Conclusion

Our data suggest that a protocol consisting of mitochondrial-targeted cofactors (co-enzyme Q10 and L-carnitine) plus amitriptyline (or possibly cyproheptadine in preschoolers) coupled with blood level monitoring is highly effective in the prevention of vomiting episodes.

Cyclic vomiting syndrome is characterized by recurrent episodes of stereotyped vomiting separated by regular symptom-free periods. We describe a case of cyclic vomiting syndrome developed after stroke, which has not been reported to date. A 69-year-old woman experienced recurrent vomiting following left cerebral infarct. The patient's vomiting pattern was consistent with cyclic vomiting syndrome, and the diagnosis of cyclic vomiting syndrome was established by exclusion of other known disorders which could have resulted in vomiting. She was treated with imipramine hydrochloride and her symptom was well controlled.

Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent episodes of incapacitating nausea and vomiting interspersed with symptom free periods. Common triggers of cyclic vomiting include noxious stress, excitement, fatigue and menstrual period. Here, we report a case of cyclic vomiting syndrome in adult patient characterized by stereotypical vomiting attack, occurring in every menstruation period. Recurrent vomiting episodes began 6 years ago and we treated this patient with subcutaneous injection of goserelin, a gonadotropin-releasing hormone analogue (GnRHa) and oral estrogen. After 4 months of therapy, she was symptom free for the following 5 years, even with the resumed normal menstruation. Recurrence of vomiting attack with same pattern occurred 1 month before readmission. Treatment with intravenous lorazepam aborted vomiting, but could not prevent recurrences of vomiting and epigastric pain. We treated the patient with GnRHa and oral estradiol again which effectively prevented recurrence of the symptoms.

Background

Cyclical Vomiting Syndrome (CVS) is characterised by discrete, unexplained episodes of intense nausea and vomiting, and mainly affects children and adolescents. Comprehending Cyclical Vomiting Syndrome requires awareness of the severity of nausea experienced by patients. As a subjective symptom, nausea is easily overlooked, yet is the most distressing symptom for patients and causes many behavioural changes during attacks.

Case presentation

This first-hand account of one patient's experience of Cyclical Vomiting Syndrome shows how severe nausea contributed to the development of anticipatory nausea and vomiting (ANV), a conditioned response frequently observed in chemotherapy patients. This conditioning apparently worsened the course of the patient's disease. Anticipatory nausea and vomiting has not previously been recognised in Cyclical Vomiting Syndrome, however predictors of its occurrence in oncology patients indicate that it could complicate many cases.

Conclusion

We suggest a model whereby untreated severe and prolonged nausea provokes anxiety about further cyclical vomiting attacks. This anxiety facilitates conditioning, thus increasing the range of triggers in a self-perpetuating manner. Effective management of the nausea-anxiety feedback loop can reduce the likelihood of anticipatory nausea and vomiting developing in other patients.

Cyclic vomiting syndrome is an increasingly recognized cause of nausea and vomiting in adults. We report the case of a 47-year-old man with recurrent episodes of intractable nausea and vomiting for one year. His symptoms persisted for 4–7 days and then resolved spontaneously, only to return after periods of time ranging from one week up to a month. After an extensive workup, which failed to determine any causative explanation for his symptoms, he was diagnosed with cyclic vomiting syndrome. His episodes of vomiting were successfully terminated with the use of intranasal sumatriptan. In this case, we highlight that sumatriptan effectively aborted symptoms in an adult patient with cyclic vomiting syndrome. Increasing physicians’ awareness of adult cyclic vomiting syndrome may improve care of patients suffering from this debilitating condition.

Cyclic vomiting syndrome (CVS) is a condition whose symptoms are recurring attacks of intense nausea, vomiting and sometimes abdominal pain and/or headaches or migraines. Cyclic vomiting usually develops during the childhood ages of 3 - 7; whereas it often remits during adolescence, it can persist into adult life. We report a case of a 57 years old Caucasian male with a history of renal cell carcinoma status post left nephrectomy presenting with a 7 years history of intermittent nausea and vomiting with prodromal malaise, watery diarrhea, flushing and diaphoresis. Cyclic vomiting syndrome is a debilitating functional brain-gut disorder that was initially characterized in children, but now is increasingly recognized to occur also in adults.

Keywords

Cyclic vomiting syndrome; Vomitting; Post nephrectomy

11 children with either cystinosis or Lowe's syndrome had a reduced content of plasma and muscle carnitine due to renal Fanconi syndrome. After treatment with oral L-carnitine, 100 mg/kg per d divided every 6 h, plasma carnitine concentrations became normal in all subjects within 2 d. Initial plasma free fatty acid concentrations, inversely related to free carnitine concentrations, were reduced after 7-20 mo of carnitine therapy. Muscle lipid accumulation, which varied directly with duration of carnitine deficiency (r = 0.73), improved significantly in three of seven rebiopsied patients after carnitine therapy. One Lowe's syndrome patient achieved a normal muscle carnitine level after therapy. Muscle carnitine levels remained low in all cystinosis patients, even though cystinotic muscle cells in culture took up L-[3H]carnitine normally. The half-life of plasma carnitine for cystinotic children given a single oral dose approximated 6.3 h; 14% of ingested L-carnitine was excreted within 24 h. Studies in a uremic patient with cystinosis showed that her plasma carnitine was in equilibrium with some larger compartment and may have been maintained by release of carnitine from the muscle during dialysis. Because oral L-carnitine corrects plasma carnitine deficiency, lowers plasma free fatty acid concentrations, and reverses muscle lipid accumulation in some patients, its use as therapy in renal Fanconi syndrome should be considered. However, its efficacy in restoring muscle carnitine to normal, and the optimal dosage regimen, have yet to be determined.

Images

Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder that can occur in both children and adults. Clinical courses of CVS manifesting recurrent severe vomiting episodes and interval illness may affect the long-term quality of life in children with CVS. Therefore, we should be careful in accessing a patient suggestive of CVS. Accurate diagnosis based on diagnostic criteria for CVS and the exclusion from other organic diseases mimicking clinical manifestations of cyclic vomiting is absolutely required. In patients diagnosed as CVS, optimal therapy should be performed to improve symptoms and to reduce complications in prodromal phase and emetic phase, and long-term prophylactic therapy should be tried to prevent the development of vomiting episodes. The identification of triggering factors which induce vomiting episodes might be helpful in preventing vomiting attacks. Systematic approach should be recommended to improve clinical outcome of CVS.

The aim of this case report was to evaluate the psychiatric co-morbidity and efficacy of mirtazapine treatment in young subjects with chronic or cyclic vomiting syndromes. This is a case series of 8 young subjects (age range of 6-16 years, 11.12 ± 3.52 years) who were referred or consulted to child psychiatry department. They were referred or consulted by pediatric gastroenterology or surgery departments for the presence of non-remitting and medically unexplained vomiting. They were investigated for co-morbid psychiatric disorders using a structured psychiatric interview. An open trial of mirtazapine was conducted for the treatment and/or prevention of vomiting. Primary outcome measure was Clinical Global Impression-Improvement scale. Subjects were diagnosed with chronic (n = 5) or cyclic (n = 3) vomiting syndromes. Duration of vomiting ranged from 6 months to 10 years (3.5 ± 3.2 years). All subjects received multiple psychiatric diagnoses with anxiety disorders being the most frequent. Maximum mirtazapine dosage was 7.5-30 mg/day (16.00 ± 6.16 mg/day). Three subjects showed complete remission and 5 subjects showed much to very much improvement in vomiting. Most frequent side effects were increased appetite, weight gain and sedation. Young subjects with chronic or cyclic vomiting may frequently suffer anxiety and/or depressive symptoms or disorders. Mirtazapine could be an effective treatment option for the treatment of vomiting and co-morbid anxiety or depressive disorders in these subjects. More systematic research are needed on this topic.

Introduction

Posterior reversible encephalopathy syndrome is characterized by headache, nausea and vomiting, seizures and visual disturbances. It has certain characteristic radiological features, which allow diagnosis in the appropriate clinical setting and enable appropriate clinical therapy to be instituted.

Case presentation

A 10-year-old Caucasian girl who was hospitalized due to recurrent vomiting was diagnosed as having posterior reversible encephalopathy syndrome after an initial diagnosis of cyclical vomiting and hypertension was made.

Conclusion

Posterior reversible encephalopathy syndrome is a rare disorder in children. Early recognition of characteristic radiological features is key to the diagnosis as clinical symptoms may be non-specific or mimic other neurological illnesses. To the best of our knowledge this is the first case to report an association between posterior reversible encephalopathy syndrome, cyclical vomiting and hypertension. Furthermore, in this case, the resolution of the abnormalities found on magnetic resonance imaging over time did not appear to equate with clinical recovery.

Cannabis is a common drug of abuse that is associated with various long-term and short-term adverse effects. The nature of its association with vomiting after chronic abuse is obscure and is underrecognised by clinicians. In some patients this vomiting can take on a pattern similar to cyclic vomiting syndrome with a peculiar compulsive hot bathing pattern, which relieves intense feelings of nausea and accompanying symptoms. In this case report, we describe a twenty-two year-old-male with a history of chronic cannabis abuse presenting with recurrent vomiting, intense nausea and abdominal pain. In addition, the patient reported that the hot baths improved his symptoms during these episodes. Abstinence from cannabis led to resolution of the vomiting symptoms and abdominal pain. We conclude that in the setting of chronic cannabis abuse, patients presenting with chronic severe nausea and vomiting that can sometimes be accompanied by abdominal pain and compulsive hot bathing behaviour, in the absence of other obvious causes, a diagnosis of cannabinoid hyperemesis syndrome should be considered.

Plasma and urine free and acyl carnitine were measured in 19 children with nephropathic cystinosis and renal Fanconi syndrome. Each patient exhibited a deficiency of plasma free carnitine (mean 11.7 +/- 4.0 [SD] nmol/ml) compared with normal control values (42.0 +/- 9.0 nmol/ml) (P less than 0.001). Mean plasma acyl carnitine in the cystinotic subjects was normal. Four subjects with Fanconi syndrome but not cystinosis displayed the same abnormal pattern of plasma carnitine levels; controls with acidosis or a lysosomal storage disorder (Fabry disease), but not Fanconi syndrome, had entirely normal plasma carnitine levels. Two postrenal transplant subjects with cystinosis but without Fanconi syndrome also had normal plasma carnitine levels. Absolute amounts of urinary free carnitine were elevated in cystinotic individuals with Fanconi syndrome. In all 21 subjects with several different etiologies for the Fanconi syndrome, the mean fractional excretion of free carnitine (33%) as well as acyl carnitine (26%) greatly exceeded normal values (3 and 5%, respectively). Total free carnitine excretion in Fanconi syndrome patients correlated with total amino acid excretion (r = 0.76). Two cystinotic patients fasted for 24 h and one idiopathic Fanconi syndrome patient fasted for 5 h showed normal increases in plasma beta-hydroxybutyrate and acetoacetate, which suggested that hepatic fatty acid oxidation was intact despite very low plasma free carnitine levels. Muscle biopsies from two cystinotic subjects with Fanconi syndrome and plasma carnitine deficiency had 8.5 and 13.1 nmol free carnitine per milligram of noncollagen protein, respectively (normal controls, 22.3 and 17.1); total carnitines were 11.8 and 13.3 nmol/mg noncollagen protein (controls 33.5, 20.0). One biopsy revealed a mild increase in lipid droplets. The other showed mild myopathic features with variation in muscle fiber size, small vacuoles, and an increase in lipid droplets. In renal Fanconi syndrome, failure to reabsorb free and acyl carnitine results in a secondary plasma and muscle free carnitine deficiency.

Images

The human primary carnitine deficiency syndromes are potentially fatal disorders affecting children and adults. The molecular etiologies of these syndromes have not been determined. In this investigation, we considered the hypothesis that these syndromes result from defective transport of carnitine into tissues, particularly skeletal muscle. The problem was approached by mathematical modeling, by using the technique of kinetic compartmental analysis. A tracer dose of L-[methyl-3H]carnitine was administered intravenously to six normal subjects, one patient with primary muscle carnitine deficiency (MCD), and four patients with primary systemic carnitine deficiency (SCD). Specific radioactivity was followed in plasma for 28 d. A three-compartment model (extracellular fluid, muscle, and "other tissues") was adopted. Rate constants, fluxes, pool sizes, and turnover times were calculated. Results of these calculations indicated reduced transport of carnitine into muscle in both forms of primary carnitine deficiency. However, in SCD, the reduced rate of carnitine transport was attributed to reduced plasma carnitine concentration. In MCD, the results are consistent with an intrinsic defect in the transport process. Abnormal fluctuations of the plasma carnitine, but of a different form, occurred in MCD and SCD. The significance of these are unclear, but in SCD they suggest abnormal regulation of the muscle/plasma carnitine concentration gradient. In 8 of 11 subjects, carnitine excretion was less than dietary carnitine intake. Carnitine excretion rates calculated by kinetic compartmental analysis were higher than corresponding rates measured directly, indicating degradation of carnitine. However, we found no radioactive metabolites of L-[methyl-3H]carnitine in urine. These observations suggest that dietary carnitine was metabolized in the gastrointestinal tract.

In addition to hemorrhagic cystitis, Fanconi Syndrome is a serious clinical side effect during ifosfamide (IFO) therapy. Fanconi syndrome is a generalized dysfunction of the proximal tubule which is characterized by excessive urinary excretion of glucose, phosphate, bicarbonate, amino acids and other solutes excreted by this segment of the nephron including L-carnitine. Carnitine is essential cofactor for β-oxidation of long-chain fatty acids in the myocardium. IFO therapy is associated with increased urinary carnitine excretion with subsequent secondary deficiency of the molecule. Cardiac abnormalities in IFO-treated cancer patients were reported as isolated clinical cases. This study examined whether carnitine deficiency and oxidative stress, secondary to Fanconi Syndrome, provoke IFO-induced cardiomyopathy as well as exploring if carnitine supplementation using Propionyl-L-carnitine (PLC) could offer protection against this toxicity. In the current study, an animal model of carnitine deficiency was developed in rats by D-carnitine-mildronate treatment Adult male Wistar albino rats were assigned to one of six treatment groups: the first three groups were injected intraperitoneally with normal saline, D-carnitine (DC, 250 mg/kg/day) combined with mildronate (MD, 200 mg/kg/day) and PLC (250 mg/kg/day), respectively, for 10 successive days. The 4th, 5th and 6th groups were injected with the same doses of normal saline, DC-MD and PLC, respectively for 5 successive days before and 5 days concomitant with IFO (50 mg/kg/day). IFO significantly increased serum creatinine, blood urea nitrogen (BUN), urinary carnitine excretion and clearance, creatine phosphokinase isoenzyme (CK-MB), lactate dehydrogenase (LDH), intramitochondrial acetyl-CoA/CoA-SH and thiobarbituric acid reactive substances (TBARS) in cardiac tissues and significantly decreased adenosine triphosphate (ATP) and total carnitine and reduced glutathione (GSH) content in cardiac tissues. In carnitine-depleted rats, IFO induced dramatic increase in serum creatinine, BUN, CK-MB, LDH, carnitine clearance and intramitochondrial acetyl-CoA/CoA-SH, as well as progressive reduction in total carnitine and ATP in cardiac tissues. Interestingly, PLC supplementation completely reversed the biochemical changes-induced by IFO to the control values. In conclusion, data from the present study suggest that: Carnitine deficiency and oxidative stress, secondary to Fanconi Syndrome, constitute risk factors and should be viewed as mechanisms during development of IFO-induced cardiotoxicity. Carnitine supplementation, using PLC, prevents the development of IFO-induced cardiotoxicity through antioxidant signalling and improving mitochondrial function.

Objective

The purpose of this case report is to describe chiropractic management of a child with cyclic vomiting syndrome.

Clinical Features

A 7-year-old girl had a history of cyclic vomiting episodes for the past 4 1/2 years. She also had a 2-month history of headaches and stomachache.

Intervention and Outcome

The patient received low-force chiropractic spinal manipulation to her upper cervical spine. There was improvement in her symptoms within an hour after the chiropractic manipulation. Her symptoms only returned after direct trauma to her neck. The recurring symptoms again disappeared immediately after treatment.

Conclusion

This case study suggests that there may be a role for the use of chiropractic spinal manipulative therapy for treating cyclic vomiting syndrome. Controlled studies are necessary to aid our understanding of this finding.

Background

Cyclic vomiting syndrome (CVS), a chronic disorder characterized by recurrent episodes of vomiting, is frequently unrecognized and is associated with high utilization of emergency department (ED) services.

Methods

A web-based survey was posted on the Cyclic Vomiting Syndrome Association (CVSA) website to assess utilization of ED services in patients with CVS.

Results

Of 251 respondents, 104 (41.4%) were adult CVS patients and 147 (58.6%) were caregivers of pediatric and adult patients. In the adult group, the median number of ED visits for CVS symptoms was 15(range 1 - 200), with a median of 7 ED visits prior to a diagnosis of CVS (range 0 - 150). In the caregiver group, the median number of ED visits was 10 (range 1 - 175) and the median number of ED visits prior to a diagnosis of CVS was 5 (range 0 - 65). CVS was not diagnosed in the ED in 89/104 (93%) adults and 119/147 (93%) patients in the caregiver group. CVS was not recognized in the ED in 84/95 (88%) of adults and 97/122 (80%) of patients in the caregiver group, despite an established diagnosis of CVS.

Conclusion

There is a sub-group of adult and pediatric CVS patients who are high utilizers of ED services and CVS is not recognized in the ED in the majority of patients. Improved efforts to educate ED physicians are indicated to optimize treatment of patients with CVS and to decrease potential overuse of ED services.

Primary carnitine deficiency (PCD) is an autosomal recessive disorder of fatty acid oxidation caused by mutations in the SLC22A5 gene encoding for the carnitine transporter OCTN2. Carnitine uptake deficiency results in renal carnitine wasting and low plasma levels. PCD usually presents early in life either with acute metabolic crisis or as progressive cardiomyopathy that responds to carnitine supplementation. PCD inclusion in the newborn screening (NBS) programs has led to the identification of asymptomatic adult patients ascertained because of a positive NBS in their offspring. We extensively reviewed the literature and found that 15 of 42 adult published cases (35.7%) were symptomatic. Cardiac arrhythmias were present in five patients (12%). Here, we report the ascertainment and long-term follow-up of the first case of PCD presenting with long QT syndrome. The patient presented in her early twenties with a syncopal episode caused by ventricular tachycardia, and a prolonged QT interval. Arrhythmias were poorly controlled by pharmacologic therapy and a defibrillator was installed. Syncopal episodes escalated during her first pregnancy. A positive NBS in the patient’s child suggested a carnitine uptake deficiency, which was confirmed by reduced carnitine transporter activity and by molecular testing. After starting carnitine supplementation, no further syncopal episodes have occurred and the QT interval returned to normal. As precaution, a low-dose metoprolol therapy and the defibrillator are still in place. Although rare, PCD should be ruled out as a cause of cardiac arrhythmias since oral carnitine supplementation is readily available and efficient.

Background

Cyclic vomiting syndrome (CVS) is characterized by stereotypical episodes of vomiting separated by symptom-free intervals. However, the difficulty encountered in the management of patients with CVS may be a reflection of a deficiency in our understanding of the disorder. We aimed to evaluate whether clinical or gastric emptying (GE) data discriminate patients labeled as having CVS from functional vomiting (FV) or IBS.

Methods

The medical records of patients diagnosed with any vomiting (including CVS, FV) over a 13-year period (1993–2006) at our institution were carefully reviewed. Disease controls were age and gender matched subjects with IBS. GE was performed by scintigraphy (99mTc-egg meal). The associations of clinical factors and gastric emptying data with patient status (CVS vs. FV or IBS) were analyzed.

Key Results

A total of 82 patients with CVS and 62 FV patients were identified. Younger age (per 10 years, OR=0.7 [0.5, 0.9]), male gender (OR=0.4 [0.2, 0.9]), and cannabinoid use (OR=2.9 [1.2, 7.2]) were significantly associated with CVS compared to FV. However, there were no significant associations between patient status (CVS vs. FV) and age, BMI, smoking, alcohol use, gastrointestinal symptoms, or GE. The proportion of cannabinoid users was significantly higher in subjects with CVS compared to subjects with IBS, while proportions for headaches and psychiatric disease were higher in subjects with IBS.

Conclusions

CVS (vs. FV) was not associated with clinical factors, but was associated with younger age, male gender and cannabinoid use. A larger proportion of CVS (vs. IBS) patients had used cannabinoids.

Cannabinoid hyperemesis syndrome is characterized by chronic, heavy use of cannabis, recurrent episodes of severe nausea and intractable vomiting, and abdominal pain. Temporary relief of symptoms is achieved by taking a hot bath or shower, and resolution of the problem when cannabis use is stopped. Failure to recognize the syndrome leads to misdiagnoses such as psychogenic vomiting, the cyclic vomiting syndrome, an eating disorder or ‘drug-seeking behaviour’, and may lead to extensive, expensive and unproductive investigations, psychiatric referrals and ineffective treatments. Other than stopping cannabis use, there is no proven treatment. Why a substance known for its antiemetic properties should cause such a syndrome is unknown.

QUESTION One of my pediatric patients was diagnosed with cyclic vomiting syndrome, and the parents are understandably frustrated with the recurrent yet unpredictable episodes that control and disrupt their family life. Are there any effective treatments for this condition?

ANSWER There is currently no evidence-based treatment regimen for cyclic vomiting syndrome. Pharmacologic remedies, according to anecdotal cases, retrospective reports, and open-label trials, have found that some antimigraine, antiemetic, prokinetic, and anticonvulsant agents have been effective. Management focuses on correct diagnosis of the syndrome, avoidance of potential triggers, prophylactic pharmacotherapy, and supportive care for children and their families during episodes.

A female patient, with normal familial history, developed at the age of 30 months an episode of diarrhoea, vomiting and lethargy which resolved spontaneously. At the age of 3 years, the patient re-iterated vomiting, was sub-febrile and hypoglycemic, fell into coma, developed seizures and sequels involving right hemi-body. Urinary excretion of hexanoylglycine and suberylglycine was low during this metabolic decompensation. A study of pre- and post-prandial blood glucose and ketones over a period of 24 hours showed a normal glycaemic cycle but a failure to form ketones after 12 hours fasting, suggesting a mitochondrial β-oxidation defect. Total blood carnitine was lowered with unesterified carnitine being half of the lowest control value. A diagnosis of mild MCAD deficiency (MCADD) was based on rates of 1-14C-octanoate and 9, 10-3H-myristate oxidation and of octanoyl-CoA dehydrogenase being reduced to 25% of control values. Other mitochondrial fatty acid oxidation proteins were functionally normal. De novo acylcarnitine synthesis in whole blood samples incubated with deuterated palmitate was also typical of MCADD. Genetic studies showed that the patient was compound heterozygous with a sequence variation in both of the two ACADM alleles; one had the common c.985A>G mutation and the other had a novel c.145C>G mutation. This is the first report for the ACADM gene c.145C>G mutation: it is located in exon 3 and causes a replacement of glutamine to glutamate at position 24 of the mature protein (Q24E). Associated with heterozygosity for c.985A>G mutation, this mutation is responsible for a mild MCADD phenotype along with a clinical story corroborating the emerging literature view that patients with genotypes representing mild MCADD (high residual enzyme activity and low urinary levels of glycine conjugates), similar to some of the mild MCADDs detected by MS/MS newborn screening, may be at risk for disease presentation.

Initially described in children, cyclic vomiting syndrome (CVS) is an idiopathic disorder that affects patients of all ages and is characterized by recurrent episodes of vomiting separated by symptom-free intervals or baseline health. Frequent misdiagnoses and delays in diagnosis often lead to years of recurrent vomiting. Similarities in the clinical features and symptoms of children and adults with CVS are often linked to migraines. Association with mitochondrial disorders and neuroendocrine dysfunction have been described in the pediatric CVS literature, whereas migraines, anxiety, and panic are common in adults with CVS. Various psychological, infectious, and physical stressors commonly precipitate episodes of CVS. Treatment is mostly empiric, with few controlled therapeutic studies conducted thus far. Associations with migraines have aided in developing pharmacologic treatment strategies for prophylaxis as well as abortive therapy during episodes, including the use of trip-tans. Most children outgrow CVS with time, though some children transition to migraine headaches or continue to have CVS as adults. Improved recognition of CVS in adults, along with the emergence of data in the use of anticonvulsants and antiemetics, may help further delineate pathophysiologic connections and therapeutic options for this debilitating disorder.

Cancer cachexia is a multifaceted syndrome characterized, among many symptoms, by extensive muscle wasting. Chronic systemic inflammation, partly triggered and sustained by cytokines, as well as increased oxidative stress contributes to the pathogenesis of this complex metabolic disorder. l-carnitine plays a central role in the metabolism of fatty acids and shows important antioxidant and anti-inflammatory properties. Systemic carnitine depletion has been described in several diseases, and it is characterized by fatigue, muscle weakness, and decreased tolerance to metabolic stress. In cachectic cancer patients, low serum carnitine levels have been reported, and this change has been suggested to play an important contributory role in the development of cachexia. Based on these data, carnitine supplementation has been tested in preliminary studies concerning human cachexia, resulting in improved fatigue and quality of life. We present here a review of clinical and experimental evidence regarding the use of carnitine supplementation in the management of cancer cachexia.

Background

Carnitine deficiency or coenzyme Q10 (CoQ10) deficiency may present with hypotonia, poor growth, easy fatigability, and apnea. This constellation of findings can also be seen in individuals with Prader-Willi syndrome (PWS). Animal studies indicate that increased fat mass due to obesity negatively correlates with both carnitine and CoQ10 levels in skeletal muscle. Increased body fat and obesity are characteristic of individuals with PWS. Currently there is no documentation of serum carnitine levels, and only one study investigating plasma CoQ10 levels, in individuals with PWS.

Methods

Fasting serum carnitine and plasma CoQ10 levels were measured in 40 individuals with molecularly confirmed PWS (ages 1–27 years; 19 F/21M), 11 individuals with early-onset morbid obesity of unknown etiology (ages 3–13 years; 5F/6M), and 35 control siblings from both groups (ages 1–24 years; 19F/16M).

Results

There were no significant differences among the 3 groups in either total carnitine, free carnitine, or CoQ10 levels. However, individuals with PWS had higher serum levels of carnitine esters (p=0.013) and higher ester-to-free carnitine ratios (p=0.0096) than controls suggesting a possible underlying impairment of peripheral carnitine utilization and mitochondrial energy metabolism in some individuals with PWS.

Conclusions

Serum sampling identified no significant differences in total and free carnitine or CoQ10 levels between individuals with PWS, obese individuals, and sibling control groups. Muscle biopsy or measurement in leukocytes or cultured skin fibroblasts could be a better method to identify abnormalities in carnitine and CoQ10 metabolism in individuals with PWS than peripheral blood sampling.

Cancer cachexia is a multifaceted syndrome characterized, among many symptoms, by extensive muscle wasting. Chronic systemic inflammation, partly triggered and sustained by cytokines, as well as increased oxidative stress contributes to the pathogenesis of this complex metabolic disorder. l-carnitine plays a central role in the metabolism of fatty acids and shows important antioxidant and anti-inflammatory properties. Systemic carnitine depletion has been described in several diseases, and it is characterized by fatigue, muscle weakness, and decreased tolerance to metabolic stress. In cachectic cancer patients, low serum carnitine levels have been reported, and this change has been suggested to play an important contributory role in the development of cachexia. Based on these data, carnitine supplementation has been tested in preliminary studies concerning human cachexia, resulting in improved fatigue and quality of life. We present here a review of clinical and experimental evidence regarding the use of carnitine supplementation in the management of cancer cachexia.