Abstrak Infeksi Cryptococcus neoformans merupakan salah satu infeksi oportunistik pada penderita HIV yang dapat menyebabkan meningitis kriptokokus dan dapat dideteksi secara dini melalui antigen yang terdapat pada kapsul polisakarida. Ketersediaan pemeriksaan antigen ini sangat terbatas sehingga dibutuhkan parameter lain untuk mendeteksi secara dini kemungkinan terjadi meningitis kriptokokus. Parameter tersebut adalah C-reactive protein (CRP). Penelitian ini bertujuan untuk membandingkan kadar CRP kuantitatif dengan hasil deteksi antigen   C. neoformans pada penderita infeksi HIV. Serum diambil dari penderita HIV di klinik Teratai   RSUP Dr. Hasan Sadikin Bandung yang baru pertama kali terdeteksi, CD4+ <100 sel/mm3, belum diterapi, serta tidak didiagnosis meningitis  kriptokokus.  Dilakukan  deteksi  antigen  menggunakan  Cryptococcal  antigen  latex  agglutination system (Meridian Diagnostics) dan pemeriksaan CRP kuantitatif. Desain penelitian analitik komparatif dengan analisis statistik menggunakan   statistical product and service solutions (SPSS) ver. 13, Uji Mann-Whitney U, dan dilakukan perhitungan sensitivitas dan spesifisitas serta penentuan cut-off CRP kuantitatif dengan kurva ROC. Hasil penelitian menunjukkan perbedaan bermakna kadar CRP kuantitatif pada hasil CALAS positif dengan negatif. Kadar CRP pada CALAS positif lebih tinggi dibandingkan dengan CALAS negatif (p<0,05). Dari kurva ROC didapatkan sensitivitas 84,3% dan spesifisitas 42,4%, serta cut-off CRP >5,8197 mg/dL. Dari 14 sampel dengan CALAS positif, 12 (85,7 %) dengan CRP >5,8197 mg/dL dan  2 (14,3%)  dengan CRP â¤5,8197 mg/dL. Simpulan, CRP kuantitatif dapat  dipertimbangkan sebagai salah satu parameter untuk mendeteksi secara dini kemungkinan meningitis kriptokokus pada pasien HIV dengan menyingkirkan  kemungkinan lain yang dapat mengakibatkan peningkatan CRP.   Kata kunci: Cryptococcal antigen latex agglutination system, C-reactive protein, meningitis kriptokokus Comparison of Quantitative C-Reactive Protein Concentration and Cryptococcus neoformans Antigen Detection Results in Human Immunodeficiency Virus Patients   Abstract Cryptococcus neoformans infection is one of the opportunistic infections in HIV patients, it caused cryptococcal meningitis, which can be detected earlier using the antigen contained in the polysacharide capsule. The availability of this antigen test is very limited that other parameter are needed for early detection of cryptococcal meningitis. That parameter is C-reactive protein (CRP). The aim of this study was to compare the levels of quantitative CRP with the  C. neoformans antigen detection in HIV patients. This was a comparative analytical study design using serum taken from HIV patients who came to the Teratai Clinic RSUP Dr. Hasan Sadikin Bandung. The inclusion criteria was subject on their first detection having  CD4 + <100 cells/mm3, have never been treated before and was not diagnosed with cryptococcal meningitis. Cryptococcal antigen detection using antigen latex agglutination system (Meridian Diagnostics) and quantitative CRP examination was performed. Data analysis used statistical analysis statistical product and service solution (SPSS) ver. 13 to calculate sensitivity and specificity and the determination of CRP cut-off by ROC curve. Results showed that there was significant differences in the levels of quantitative CRP from positive and negative CALAS results. CRP levels in CALAS positive results was higher than negative result (p<0.05). From ROC curve, the CRP had 84.3% sensitivity  and 42.4% specificity, and the cut-off was >5.8197 mg/ dL. Of 14 samples with positive CALAS result, 12 (85.7%) had CRP >5.8197 mg/dL and 2 (14.3%) with CRP â¤5.8197 mg/dL. In conclusion, quantitative CRP could be considered as a parameter for early detection of cryptococcal meningitis in HIV patients, by eliminating the possibilities that can lead to increased level of CRP.   Key words: C-reactive protein, Cryptococcal antigen latex agglutination system, cryptococcal meningitisÂ