orthorexia nervosa is an obsession for healthy food which may lead to strict diets , sometimes with a shortage of essential nutrients . patients with orthorexia nervosa are worried about quality of food , in contrast patients with anorexia and bulimia are worried about its quantity1 ) . patients with malnutrition due to anorexia nervosa were reported with severe hyponatremia2 ) , hypokalemia with renal potassium wasting , and metabolic acidosis with a normal plasma anion gap3 ) , subcutaneous emphysema , mediastinal emphysema , pneumothorax4 ) , and pancytopenia5 ) . refeeding syndrome is defined as the potentially fatal shifts in fluids and electrolytes that may occur in malnourished patients by aggressive reinstitution of nutritional support6 ) . refeeding syndrome characterizes abnormal sodium and fluid balance , changes in glucose , protein , and fat metabolism , thiamine deficiency , hypokalaemia , and hypomagnesaemia along with alterations in neurologic , cardiac , hematologic , neuromuscular , and pulmonary function6 ) . we report a patient with orthorexia nervosa who developed hyponatremia , metabolic acidosis , subcutaneous emphysema , mediastinal emphysema , pneumothorax , and pancytopenia and we review the literature . also , we discuss preventive measures in refeeding syndrome , to identify high risk patients and introduce american and european guidelines . case : a 30-year - old male was admitted to our hospital with general weakness and drowsy mental status . he had eaten only 3 - 4 spoons of brown rice and fresh vegetable without salt for 3 months to treat his tic disorder , and he had been in bed - ridden state . he had taken propolis and enema by himself , and his past medical history was unremarkable except tic disorder since high school . his blood pressure was 100/70 mm hg , pulse rate 72/min , and respiratory rate 18/min , body temperature 36. he had lost 14 kg in the past 3 months . serum laboratory results were as follows ; hemoglobin 16.2 g / dl , white blood cell ( wbc ) 4.9  10/l , platelet 201  10/l , total protein 5.6 g / dl , albumin 3.4 g / dl , aspartate aminotransferase ( ast ) 114 iu / l , alanine aminotransferase ( alt ) 101 iu / l , alkaline phosphatase ( alp ) 57 iu / l , -glutamyl transferase ( ggt ) 13 iu / l , bilirubin ( total / direct ) 3.22/0.8 mg / dl , glucose 166 mg / dl , amylase 98 iu / l , blood urea nitrogen ( bun ) 33.6 mg / dl , creatinine 0.41 mg / dl , total co2 20.2 meq / l , sodium 101 meq / l , potassium 4.0 meq / l , chloride 68 meq / l , calcium 6.8 mg / dl , inorganic phosphorus 2.7 mg / dl , magnesium 1.5 meq / l , uric acid 1.0 mg / dl , c - reactive protein ( crp ) 1.87 mg / dl , osmolality 213 mosm / kg h2o , creatine phosphokinase ( cpk ) 1,472 iu / l ( 29 - 145 ) , myoglobin 1,278 ng / ml , lactate dehydrogenase ( ldh ) 1,472 iu / l ( 0 - 500 ) , total cholesterol 231 mg / dl , triglyceride 97 mg / dl , high density lipoprotein ( hdl)-cholesterol 127 mg / dl , low density lipoprotein ( ldl)-cholesterol 83 mg / dl , prealbumin 10.7 mg / dl , hemoglobin a1c 5.4% , thyroid stimulating hormone ( tsh ) 1.26 uiu / ml , free t4 0.75 ng / dl , and international normalized ratio ( inr ) 1.61 . urinalysis revealed a specific gravity of 1.012 , ph 7.0 , trace protein , glucose 2 + , occult blood 3 + , myoglobin 2,687 ng / m , urine sodium 62 meq / l , potassium 34.4 meq / l , chloride 43.1 meq / l , and osmolality 484 mosm / kg h2o . chest ap x - ray showed mediastinal emphysema and extensive soft tissue emphysema in his neck and chest wall . abdominal ultrasonography revealed a small amount of ascites and small amount of fluid collection in his bilateral perinephric space . chest ct showed extensive soft tissue emphysema in his neck and chest wall , extensive mediastinal emphysema , small right pneumothorax , and pericardial fluid ( fig . 1 ) . to rule out esophageal perforation esophagography with gastrographin was performed and it showed no evidence of contrast leakage from his esophagus . the diagnosis of orthorexia nervosa with hyponatremia , rhabdomyolysis , pneumomediastinum , pneumothorax , and soft tissue emphysema was made . we started on intravenous fluid supplementation based on treatment of hyponatremia and refeeding syndrome , and oral feeding . he gradually improved , but his total protein and albumin decreased on the 5 hospital day to 4.4 g / dl and 2.5 g / dl , respectively . on the 7 hospital day , his platelet and wbc levels decreased to 27  10/l and 1.2  10/l , respectively . on the 12 hospital day peripheral blood smear showed normochromic normocytic anemia with anisopoikilocytosis 2 + , neutropenia , lymphocytopenia , relative monocytosis 14% , and thrombocytopenia . his iron level was 88 g / dl , total iron binding capacity ( tibc ) 168 g / dl , ferritin 908.6 ng / ml , vitamin b12 988 pg / ml , folate 2.8 ng / ml , and his coomb 's test , plasma hemoglobin , haptoglobin , and serology were within normal limits . we transfused 6 units of platelet concentrate by his hospital 7 day and granulocyte colony - stimulating factor ( g - csf ) 150 g due to absolute neutrophil count ( anc ) 560 and methicillin - susceptible staphylococcus aureus ( mssa ) bacteremia by his hospital 16 day . by his hospital 8 day , serum laboratory results were as follows ; sodium 138 meq / l , potassium 3.7 meq / l , chloride 99 meq / l , calcium 8.1 mg / dl , inorganic phosphorus 1.9 mg / dl , magnesium 1.4 meq / l , total co2 32.5 meq / l , osmolality 271 mosm / kg h2o , cpk 270 iu / l , myoglobin 57.8 ng / ml , ldh 1,011 iu / l , and total cholesterol 140 mg / dl . by hospital 18 day , his ast level was 25 iu / l , alt 59 iu / l , alp 89 iu / l , bilirubin ( total / direct ) 0.35/0.12 mg / dl , and by hospital 28 day , his ldh was 514 iu / l . until his hospital 20 day , his platelet level steadily increased to 1,475  10/l , and gradually decreased to 382  10/l by the hospital 37 day . by his hospital 37 day , his hemoglobin increased to 12.1 g / dl and wbc also stabilized to 3.4  10/l ( neutrophil 48% ) . he was discharged by his hospital 38 day in an improving state , and followed up at our rehabilitation department for physical therapy and psychological department for supportive therapy . patients with anorexia nervosa were reported as severe hyponatremia due to 1 ) inadequate fluid and sodium intake from anorectic behaviors and dehydration from self - induced vomiting , laxative or diuretic abuse , 2 ) excessive consumption of water due to hunger , 3 ) syndrome of inappropriate secretion of antidiuretic hormone ( siadh ) by selective serotonin reuptake inhibitors ( ssris ) and phenothiazines , and 4 ) impaired water diuresis due to low protein intake2,7 ) . especially , the physiology of water diuresis is impaired at multiple levels in patients with anorexia nervosa2 ) . low blood urea nitrogen from low protein intake decreases the glomerular filtration pressure and medullary hypertonicity . sodium reabsorption is impaired in the proximal tubule due to solute delivery by low glomerular filtration2 ) , and in the thin ascending loop of henle due to diminished medullary hypertonicity2 ) . furthermore , the chronic hyponatremic state can often persist due to a " resetting of the osmostat " in response to a low serum osmolality2 ) . in patients with anorexia nervosa diminished water diuresis patients with anorexia nervosa may be complicated with central pontine myelinolysis in the absence of obvious neurologic deficits by rapid correction8 ) . to avoid brain damage , sodium should be substituted at a speed not exceeding 0.5 meq / l / hour8 ) . the pathogenesis of rhabdomyolysis due to hyponatremia is thought to be a result of hypo - osmolality of the extracellular fluid , leading to muscle cell swelling9 ) . after the cellular swelling normalizes , as a result of extrusion of intracellular potassium , the potassium - depleted muscle cells fail to release potassium , and blood flow becomes insufficient9 ) . the cellular transmembrane potential is decreased , leading to release of creatine kinase and myoglobin9 ) . the hco3 buffer system selectively removes h. two factors in this patient could contribute to poor buffering of h ; 1 ) a contracted extracellular fluid ( ecf ) volume can lead to a lower blood flow rate and to a high capillary and intracellular pco2 , 2 ) although most intracellular fluid ( icf ) buffering occurs in skeletal muscle , our patient was emaciated , and thus , his buffer capacity was markedly reduced3 ) . this probably led to a more severe degree of acidemia for a given deficit of nahco3 . it was advisable to treat his metabolic acidosis with isotonic saline to remove the limitation of a high tissue pco2 on his icf hco3 buffer system3 ) . our patient revealed extensive soft tissue emphysema in his neck and chest wall , extensive mediastinal emphysema , and a small amount of right pneumothorax . comorbidity of anorexia nervosa with pneuumomediastinum or pneumothorax rarely has been described in the literature4 ) . malnutrition of anorexia nervosa can lead to a heightened proneness to emphysema and rupture of pulmonary tissue by empty vomiting and oral manipulation leading to injury of the oral cavity4 ) . our patient had spontaneous emphysema and pneumothorax , and we conservatively treated the patient with o2 therapy . during his hospital course , our patient developed pancytopenia , and improved with one dose of g - csf , and 6 units of platelet transfusion . hematologic features of anorexia nervosa are characterized by pancytopenia , bone marrow change , marrow cell necrosis , and a relative increase in lymphocytes and plasma cells . carbohydrate deficiency causes bone marrow hypoplasia with accumulation of gelatinous acid mucopolysaccharide , and protein deficiency causes hypoplasia without gelatinous transformation5 ) . anemia in anorexia nervosa is not caused by simple iron deficiency , but due to lipoprotein abnormality5 ) . leukocytopenia and a decreased rate of in vitro killing of bacteria , and impaired cell - mediated immunity , induce a widespread infection5 ) . our patient had increased ast , alt , and total bilirubin , and improved spontenously . miller et al . reported elevation of alt , 12.2% in 214 women with anorexia nervosa7 ) . refeeding syndrome is a fatal complication during artificial feeding - parenteral or enteral- in malnourished patients . potential complications of refeeding syndrome include fatal cardiac arrhythmia , systolic heart failure , respiratory insufficiency , and h ematologic derangements6 ) . during the period of prolonged starvation , this is because these minerals are mainly in the intracellular compartment , which contracts during starvation . in addition , there is a reduction in renal excretion10 - 12 ) . during refeeding insulin stimulates the absorption of potassium into the cells through the sodium - potassium atpase symporter , which also transports glucose into the cells . these processes result in a decrease in the serum levels of phosphate , potassium , and magnesium ; all of which are already depleted6,10 - 12 ) . the clinical features of the refeeding syndrome occur as a result of the functional deficits of these electrolytes and the rapid change in basal metabolic rate . although all vitamin deficiencies may occur at variable rates with inadequate intake , thiamine is of most importance in complications of refeeding . thiamine deficiency results in wernicke 's encephalopathy ( ocular abnormalities , ataxia , confusional state , hypothermia , coma ) or korsakoff 's syndrome ( retrograde and anterograde amnesia , confabulation)10 - 12 ) . criteria from the guidelines of the national institute for health and clinical excellence ( nice ) for identifying patients at high risk of refeeding problems are one or more of the following : body mass index < 16 kg / m , unintentional weight loss > 15% in the past 3 to 6 months , little or no nutritional intake for > 10 days , and low levels of potassium , phosphate , or magnesium before feeding10 ) . patients at high risk of refeeding problems are two or more of the following : body mass index < 18.5 kg / m , unintentional weight loss > 10% in the past 3 to 6 months , little or no nutritional intake for > 5 days , and history of alcohol misuse or drugs , including insulin , chemotherapy , antacids , or diuretics10 ) . before feeding starts , nice recommends administering thiamine 200 - 300 mg daily orally , vitamin b high potency 1 - 2 tablets 3 times daily or full dose intravenous vitamin b , and multivitamin or trace element supplement once daily10 ) . mj / kg / day ( 10 kcal / kg / day , no more than 50% of energy requirements , in patients with body mass index < 14 or a negligible intake for 2 weeks or more nice recommend to start feeding 0.021 mj / kg/24 hrs ) , and slowly increasing feeding over 4 - 7 days10 ) . nice recommends rehydrating carefully and supplementing and/or correcting levels of potassium ( give 2 - 4 meq / kg / day ) , phosphate ( 0.3 - 0.6 mmol / kg / day ) , calcium , and magnesium ( 0.2 mmol / kg / day intravenously or 0.4 mmol / kg / day orally)10 ) . nice recommends monitoring potassium , phosphate , calcium , and magnesium for the first 2 weeks , and amending treatment as needed10 ) . european guidelines recommend restricting fluid to maintain renal function , replacing deficits or losses , and avoiding weight gain , that is zero balance . patients usually need 20 - 30 ml / kg / day during days 1 - 311 ) . . if edema develops , further restriction during days 1 - 3 should be done11 ) . european guidelines recommend that iron should not be supplemented in the first week during days 1 - 311 ) . european guidelines recommend that energy 15 - 20 kcal / kg / day , phosphate 30 - 50 mmol iv over 12 hours in phosphorus < 0.5 mmol / l , mgso4 24 mmol iv over 12 hours in mg < 0.5 mmol / l , kcl 20 - 40 meq iv over 4 hours in potassium < 3.5 meq / l , and fluid 25 - 30 ml / kg / day during days 4 - 6 should be done11 ) . european guidelines recommend that energy 20 - 30 kcal / kg / day , iron supplementation from day 7 , and fluid 30 ml / kg / day during days 7 - 10 should be done11 ) . in conclusion , , we should evaluate the comorbidity , and consider the possibility of refeeding syndrome to eliminate fatal complications , and start feeding and behavior therapy .
30-year - old male was admitted with general weakness and drowsy mental status . 
 he had eaten only 3 - 4 spoons of brown rice and fresh vegetable without salt for 3 months to treat his tic disorder , and he had been in bed - ridden state . 
 he has had weight loss of 14 kg in the last 3 months . 
 we report a patient with orthorexia nervosa who developed hyponatremia , metabolic acidosis , subcutaneous emphysema , mediastinal emphysema , pneumothorax , and pancytopenia and we will review the literature . also , we mention to prevent refeeding syndrome , and to start and maintain feeding in malnourished patients .