primary sjogren 's syndrome ( pss ) is a relatively common autoimmune disease affecting 23% of the adult population .
undiagnosed pss presenting with severe hypokalemia and demyelination in the absence of dryness is rare but can occur in 27% .
a 36-year - old lady presented with weakness of upper and lower limbs progressing to complete inability to move her limbs over a 12-h period .
she did not report diplopia or urinary retention and denied any fever , neck pain , or trauma .
she was a homemaker , did not smoke and denied any alcohol or substance abuse .
she was diagnosed with postviral encephalomyelitis 3 years ago and treated with steroids with complete resolution of symptoms and signs .
she had normal menstrual cycles and had one spontaneous second trimester abortion 8 years ago .
she had one living child and had undergone tubal ligation after medical termination of pregnancy 4 months prior to this presentation . on evaluation , she was afebrile , normotensive with a respiratory rate of 25-breaths / min and resting pulse oximetry of 98% . there was flaring of alae nasi during quiet respiration .
mini - mental state examination was normal , and there was no evidence of cranial nerve deficits .
power was 2/5 on the medical research council scale in the proximal muscles of the upper limbs and 1/5 in the lower limbs throughout .
arterial blood gas showed combined respiratory and normal anion gap acidosis ( ph 7.23 , paco2 46 mmhg , pao2 88 mmhg , hco3 18 meq / l , chloride 105 meq / l , and corrected anion gap 10 meq / l ) .
she was electively intubated and ventilated for impending respiratory failure with deep venous thrombosis prophylaxis , enteral feeding , and evaluation for acute onset quadriparesis .
chest radiographs were normal , and electrocardiography showed prolonged pr interval , prominent  u  waves and  t  inversions .
meq / l ) and deranged renal function ( serum creatinine 2.1 mg / dl , normal 0.81.2 mg / dl and blood urea 60 mg / dl , normal 2040 mg / dl ) .
serum sodium , calcium , phosphate , magnesium levels , and plasma glucose were normal .
liver function tests revealed hypoalbuminemia ( 2.8 g / dl , normal 46 g / dl ) ; enzymes were normal .
urinary electrolytes showed potassium level of 45 meq / l and positive urine anion gap .
24-h urinary calcium excretion levels were elevated ( 550 mg/24-h , normal 20275 mg ) .
the absent tendon reflexes , prior neurological illness , and lack of complete improvement with potassium replacement prompted re - evaluation .
cerebrospinal fluid examination was acellular with raised proteins ( 65 mg / dl , normal 1545 mg / dl ) ; oligoclonal bands were negative .
computed tomography ( ct ) head was normal , and nerve conduction tests showed normal sensory and motor conduction .
ct -abdomen showed medullary nephrocalcinosis [ figure 1 , left ] with an incidental suprarenal inferior vena cava thrombus ( ivc ) .
magnetic resonance imaging of the head and spine with contrast showed extensive demyelination of the brain and spinal cord [ figure 2 ] .
anti - aquaporin-4 antibodies were strongly detected by enzyme - linked immunosorbent assay ( elisa ) .
pulse methylprednisolone 1 g was administered for 3 days followed by 1 mg / kg / day enteral prednisolone .
composite images of the computed tomography of the abdomen ( computed tomography , left ) at the level of the kidneys showing large chunky calcification due to medullary nephrocalcinosis related to untreated distal renal tubular acidosis and ( right , arrow ) contrast - enhanced computed tomography - abdomen showing a suprarenal inferior vena cava thrombosis magnetic resonance imaging ( left ) of the head and spine ( right ) with contrast revealed t2 hyperintensities in the left middle cerebral peduncle ( white arrow ) , superior medulla and a long segment spinal cord ( c7 t3 , block arrow ) t2 hyperintensity with mild cord swelling suggestive of demyelination she did not report ocular or oral dryness , oral ulcers , malar rash , and photosensitivity or joint pains . in view of distal renal tubular acidosis ( rta ) with nephrocalcinosis , recurrent central nervous system ( cns ) demyelination and unprovoked unusual site thrombosis , and antinuclear antibodies ( ana )
ana was 3 + by immunofluorescence with a speckled pattern ; anti - ss - a ( ro ) antibodies were positive by elisa ( 1:1280 ) .
schirmer 's i test showed normal tear flow ( > 15 mm at 5 min ) .
serum immunoglobulin levels were normal , and the results of hiv and hepatitis c antibodies by elisa were negative .
a diagnosis of pss with distal rta and medullary nephrocalcinosis , recurrent cns demyelination with quadriparesis ( neuromyelitis optica ) and respiratory failure and secondary apla syndrome with ivc thrombosis was made .
current classification criteria [ table 1 ] are specific but insensitive and may not be fulfilled in up to 1317% of the cohort with pss .
salivary scintigraphy showing markedly diminished salivary gland flow , including delayed uptake , reduced concentration , or delayed secretion of the tracer ( left ) when compared to normal ( right ) comparison of the revised aecg classification criteria and the acr criteria for sjogren s syndrome
dry eyes and dry eyes are the hallmark of this disease and 93% and 98% in large prospective series have evidence of dry eyes and dry mouth , respectively .
extraglandular manifestations are seen in a third of patients with ss , including renal involvement in 4% .
the reported prevalence of cns manifestations in ss [ table 2 ] range from 0% to 60% ; a high index of suspicion is needed .
recurrent signs and positive anti - aquaporin-4 antibodies favored ss rather than apla as the cause of cns manifestations .
spectrum of central nervous system disease in pss her further course was complicated by pseudomonas - related ventilator - acquired pneumonia and severe weakness with prolonged ventilation .
tracheostomy was performed and enoxaparin , prednisolone , piperacillin - tazobactam , pantoprazole , good hydration , enteral shohl 's solution ( 60 meq / d alkali ) , and potassium ( 40 meq / day ) were administered .
pulse cyclophosphamide 600 mg / m was initiated a week after resolution of pneumonia and continued monthly for 3 months .
she was decannulated and discharged with a proximal power of 4/5 and the international normalized ratio of 2.1 by d48 of admission .
she is ambulatory with minimal support for activities of daily living , normal renal functions , and potassium at 3 months of discharge .
oral azathioprine has been initiated along with warfarin with a plan to continue treatment for 2 years and anticoagulation for life .
 we present a middle - aged woman with a prior history of central nervous system ( cns ) demyelinating disorder who presented with an acute onset quadriparesis and respiratory failure . 
 the evaluation revealed distal renal tubular acidosis with hypokalemia and medullary nephrocalcinosis . 
 weakness persisted despite potassium correction , and ongoing evaluation confirmed recurrent cns and long - segment spinal cord demyelination with anti - aquaporin-4 antibodies . 
 there was no history of dry eyes or dry mouth . 
 anti - sjogren 's syndrome a antigen antibodies were elevated , and there was reduced salivary flow on scintigraphy . 
 coexistent antiphospholipid antibody syndrome with inferior vena cava thrombosis was also found on evaluation . 
 the index patient highlights several rare manifestations of primary sjogren 's syndrome ( pss ) as the presenting features and highlights the differential diagnosis of the clinical syndromes in which pss should be considered in the intensive care unit . 
Introduction
Case Report
Discussion
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