By DONALD C. DRAKE ii,ou,rer .Ifr,dtcnl Kr'rter SANTO DOMINGO, Domini- can Republic-The ragged lit- tle street band filled the warm evening ;vith a scratchy Latin rhythm as one of the singers. a IO-year-old boy with a dirty shirt and forlorn voice, begged centavos from diners in tthe open-air cafe. "Dinero para la musica," the boy pleaded again and again, as people turned to avoid his insistent eyes. "Dinero para la musica." At that moient in Phila- W-h, l.jzo miles to tile north, two other Dominican children were being fllssed over and treated in one of the lvorid's finest medical fa- cihtics - the ultra monIted State&and 46 percent gf; afl'"d&hs occur among thildren under four. :hildren under' four. 1 Whooping cough, measles, fetanus, tuberculosis and diphtheria are all major child killers. But undcrlyinr! most of the illness is malnourish- Whooping cough, measles, etanus, : tuberculosis and liphtheria are all major child :illers. But underlying most d &d'iliness is malnourish- neat. It makes the children SUS- :eptibie to internal disorders, iraining water from their tis- ues, forcing them to vomit nd eventually killing them because of dehydration. Diarrhea, which is not a bediatric problem in the Jnited St@, accounted for D percent of dl Dominican leaths - child and adult I- n 1971. At the sobert Reid Cabral Iospital, the 310-bed chil- pen's hospital in Santo Dom- ngo where the twins were aken twd days after their Grth, the Rodriguezes were :old that little could be done :or their daughters in the Do- ninican Republic. The coun- ?y's medical system just ;ouIdn't handle it.. Y`fie~inedical director at the lospi&l is Dr. Hugo R. Men- Iqza, -a soft-spoken man with :entle eyes and a slight air f sadness. The government avs him $300 a month as @Cal dire&r, so in the fte&ioti he `keepi private !fifice" h&s' `2. a' common ractice here. Dr. Mendoza was giving a sitor a tour of his hospital. `hen he got to the swinging w)rs of the emergency am, he paused. "What do )LI say in English?" he ;ked. "Ah ,yes . . . Here is lr Dante's Inferno." Dramatically, he swung len ?.he double doors. Inside ere ~30 cfyir& moaning ba- ies. They were lying on five ,ng tables, a half-inch board cparating .' one from the [ext. On one side of the long ta-