diff --git a/litellm/litellm_core_utils/streaming_handler.py b/litellm/litellm_core_utils/streaming_handler.py
index 99b1c1a2ab7..07f979a063f 100644
--- a/litellm/litellm_core_utils/streaming_handler.py
+++ b/litellm/litellm_core_utils/streaming_handler.py
@@ -1451,11 +1451,7 @@ class CustomStreamWrapper:
                     setattr(
                         model_response,
                         "usage",
-                        litellm.Usage(
-                            prompt_tokens=response_obj["usage"].get("prompt_tokens", None) or None,
-                            completion_tokens=response_obj["usage"].get("completion_tokens", None) or None,
-                            total_tokens=response_obj["usage"].get("total_tokens", None) or None,
-                        ),
+                        litellm.Usage(**response_obj["usage"]),
                     )
                 elif isinstance(response_obj["usage"], Usage):
                     setattr(
diff --git a/tests/test_litellm/litellm_core_utils/test_streaming_handler.py b/tests/test_litellm/litellm_core_utils/test_streaming_handler.py
index 101935cac0a..b7091bec3c8 100644
--- a/tests/test_litellm/litellm_core_utils/test_streaming_handler.py
+++ b/tests/test_litellm/litellm_core_utils/test_streaming_handler.py
@@ -2,6 +2,7 @@ import json
 import os
 import sys
 import time
+from types import SimpleNamespace
 from unittest.mock import AsyncMock, MagicMock, Mock, patch
 
 import pytest
@@ -618,6 +619,48 @@ def test_streaming_handler_with_stop_chunk(
     assert returned_chunk is None
 
 
+def test_usage_only_openai_chunk_preserves_usage_details(
+    initialized_custom_stream_wrapper: CustomStreamWrapper,
+):
+    initialized_custom_stream_wrapper.custom_llm_provider = "openai"
+    initialized_custom_stream_wrapper.stream_options = {"include_usage": True}
+    chunk = SimpleNamespace(
+        id="chatcmpl-test",
+        model="glm-4.7",
+        choices=[],
+        usage={
+            "completion_tokens": 28,
+            "prompt_tokens": 3721,
+            "total_tokens": 3749,
+            "completion_tokens_details": {
+                "accepted_prediction_tokens": None,
+                "audio_tokens": 0,
+                "reasoning_tokens": 0,
+                "rejected_prediction_tokens": None,
+                "image_tokens": 0,
+            },
+            "prompt_tokens_details": {
+                "audio_tokens": 0,
+                "cache_write_tokens": 0,
+                "cached_tokens": 3237,
+                "video_tokens": 0,
+            },
+            "cost": 0.0003777566,
+            "is_byok": False,
+            "cost_details": {
+                "upstream_inference_cost": 0.0003777566,
+                "upstream_inference_prompt_cost": 0.0003494206,
+                "upstream_inference_completions_cost": 0.000028336,
+            },
+        },
+    )
+
+    response = initialized_custom_stream_wrapper.chunk_creator(chunk)
+
+    assert response.usage.prompt_tokens_details.cached_tokens == 3237
+    assert response.usage.completion_tokens_details.reasoning_tokens == 0
+
+
 def test_finish_reason_chunk_preserves_non_openai_attributes(
     initialized_custom_stream_wrapper: CustomStreamWrapper,
 ):