Am.  Jour.  Pharm.  ) 
July,  1909.  J 
Examination  of  Urine. 
329 
CHEMICAL  EXAMINATION  OF  A  SAMPLE  OF  URINE 
CONTAINING  PENTOSE. 
By  Charles  H.  La  Wall. 
The  urine,  which  had  a  specific  gravity  of  1.020  and  a  yellow 
color,  first  attracted  attention  by  the  abnormal  reaction  produced 
when  heated  with  Fehling's  solution,  which  was  not  reduced  to  copper 
oxide,  as  is  the  case  when  the  ordinary  carbohydrates  are  present,  but 
which  produced  a  characteristic  greenish  turbidity  and  eventually 
a  yellow  precipitate.  The  fermentation  test  gave  negative  results, 
while  a  pronounced  reduction  was  obtained  by  means  of  Boettger's 
test  with  bismuth  subnitrate  and  solution  of  potassium  hydroxide. 
A  more  extended  examination  therefore  seemed  desirable  and  about 
a  pint  of  the  urine  was  furnished,  with  a  request  for  an  exhaustive 
investigation. 
The  first  test  applied  was  the  alphanaphthol  test,  which  is  a 
group  test  for  carbohydrates  in  general.  It  is  applied  by  adding  to 
a  suspected  sample  of  urine  a  few  drops  of  a  10  per  cent,  alcoholic 
solution  of  alphanaphthol  and  then  superimposing  this  liquid  upon 
concentrated  sulphuric  acid.  In  the  presence  of  any  carbohydrate  a 
violet  zone  is  produced.   This  test  resulted  positively. 
The  Fehling  test  was  then  applied  with  the  result  as  previously 
stated.  The  reaction  showed  a  greenish  turbidity,  which  was  suc- 
ceeded by  a  yellowish  precipitate  wholly  unlike  the  normal  copper 
reduction. 
The  Boettger  test  with  bismuth  subnitrate  and  solution  of  potas- 
sium hydroxide  showed  a  marked  reduction  to  the  dark  colored 
metallic  bismuth. 
The  indigo  carmine  test  for  dextrose  gave  negative  results. 
A  fermentation  tube  showed  no  evolution  of  C02  after  twenty- 
four  hours. 
A  polariscopic  examination  of  the  sample  showed  that  it  was 
optically  inactive. 
The  phenylhydrazine  test  was  then  applied  as  follows :  A  clean, 
dry,  six  inch  test-tube  was  filled  to  the  depth  of  one-half  inch  with 
phenylhydrazine  hydrochloride,  one-half  inch  of  dried  sodium  acetate 
was  added,  and  the  tube  filled  to  half  its  capacity  with  the  urine  and 
immersed  in  a  bath  of  boiling  water  for  two  hours.  Upon  cooling 
the  contents  of  the  tube  a  voluminous  deposit  of  yellow  crystals  took 
place,  which,  when  examined  microscopically,  were  found  to  be  in 
