diff -Naur fitsio-0.9.10/setup.py fitsio-0.9.10.patched/setup.py
--- fitsio-0.9.10/setup.py	2016-08-17 14:25:57.000000000 +0200
+++ fitsio-0.9.10.patched/setup.py	2016-10-01 15:31:14.647298506 +0200
@@ -28,9 +28,9 @@
     cfitsio_dir = 'cfitsio%s' % cfitsio_version
 
     def initialize_options(self):
-        self.use_system_fitsio = False
-        self.system_fitsio_includedir = None
-        self.system_fitsio_libdir = None
+        self.use_system_fitsio = True
+        self.system_fitsio_includedir = "@INCLUDEDIR@"
+        self.system_fitsio_libdir = "@LIBDIR@"
         build_ext.initialize_options(self)    
 
     def finalize_options(self):