diff --git a/lib/orthanc.rb b/lib/orthanc.rb
index 1fb527d..0a96b2e 100644
--- a/lib/orthanc.rb
+++ b/lib/orthanc.rb
@@ -1,5 +1,6 @@
 require "orthanc/version"
 
+require 'json'
 require 'rest-client'
 require 'recursive-open-struct'
 require 'plissken'
diff --git a/lib/orthanc/client.rb b/lib/orthanc/client.rb
index 7fdd8dd..3e24bcb 100644
--- a/lib/orthanc/client.rb
+++ b/lib/orthanc/client.rb
@@ -17,8 +17,16 @@ class Client
     include Response
     attr_accessor :base_uri
 
-    def initialize(host = "localhost", port = 8042)
-      self.base_uri = RestClient::Resource.new("http://#{host}:#{port}")
+    def initialize(host = "localhost", port = 8042, user = "", password = "")
+      host = ENV['ORTHANC_HOST'] if ENV['ORTHANC_HOST'] != nil
+      port = ENV['ORTHANC_PORT'] if ENV['ORTHANC_PORT'] != nil
+      user = ENV['ORTHANC_USER'] if ENV['ORTHANC_USER'] != nil
+      password = ENV['ORTHANC_PASSWORD'] if ENV['ORTHANC_PASSWORD'] != nil
+      if user != "" && password != ""
+        self.base_uri = RestClient::Resource.new("http://#{host}:#{port}", user, password)
+      else
+        self.base_uri = RestClient::Resource.new("http://#{host}:#{port}")
+      end
     end
 
     # ------------- General -------------
diff --git a/orthanc.gemspec b/orthanc.gemspec
index 26af8d8..3d0851a 100644
--- a/orthanc.gemspec
+++ b/orthanc.gemspec
@@ -19,11 +19,11 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_development_dependency "bundler", "~> 1.9"
-  spec.add_development_dependency "rake", "~> 10.0"
+  spec.add_development_dependency "bundler", "~> 2.5"
+  spec.add_development_dependency "rake", "~> 13.2"
 
 
-  spec.add_dependency 'rest-client', "~> 1.8"
-  spec.add_dependency 'recursive-open-struct', "~> 0.6.3"
+  spec.add_dependency 'rest-client', "~> 2.1.0"
+  spec.add_dependency 'recursive-open-struct', "~> 1.1.3"
   spec.add_dependency 'plissken', "~> 0.2.0"
 end